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Interview of Frederick Seitz by Lillian Hoddeson and Paul Henriksen on 1981 January 26, Niels Bohr Library & Archives, American Institute of Physics, College Park, MD USA, www.aip.org/history-programs/niels-bohr-library/oral-histories/4877-1
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Family background and early education, motivation and funding for college; math program at Stanford University, from 1928; physics studies at California Institute of Technology; graduate study at Princeton University, beginning 1932, atmosphere of the department, faculty (Lou Turner, Eugene Wigner, John Von Neumann); colloquia, Edward Condon. Development of applications of group theory, work in solid state with Linus Pauling, Hillard B. Huntington, Albert Sherman, William Hansen, William Shockley, Robert R. Brattain, R. Bowling Barnes. Betty Seitz; work with her on the text Modern Theory of Solids. Sodium band theory work with Wigner. To University of Rochester with Lee DuBridge. Centers for solid state work including University of Michigan, University of Wisconsin, Harvard University (John Van Vleck). Work at General Electric, 1935-1936, studies of luminescence; atmosphere in industrial labs following Depression, contacts with other industrial labs; association with DuPont. State of physics in 1930s, trends at solid state centers. Work on crystal defects, pigments, leading to work on germanium and, particularly, silicon; history of study of semiconductors and influences on its development such as World War II; work on dislocations and creep; work at Westinghouse Company. World War II work with Frankford Arsenal, Dahlgren Proving Ground, and Massachusetts Institute of Technology Radiation Laboratory; University of Pennsylvania, 1938; Carnegie-Mellon University, 1942, on dark trace tubes, leading to color center papers; University of Chicago work on reactors and neutron diffraction, 1943; Oak Ridge National Laboratory with Wigner; Argonne National Laboratory, solid state group. With Field Intelligence Agency Technical (FIAT), visit to Gottingen, 1945; state of solid state physics in international centers and U.S. Return to Carnegie- Mellon; diffusion theory. Pugwash Conferences; trips to Japan, 1953 and 1962, conditions and theoretical solid state work in postwar Japan. To University of Illinois, 1949 (Wheeler Loomis); John Bardeen's work, visits by Nevill Mott and Heinz Pick; McCarthyism. Development of Seitz's bibliography, changes in the study of solid state during the 1950s.
We are beginning the first session of an interview with Dr. Seitz about his whole life, but focusing on solid state physics, which is a good part of it, at least up through the fifties. Now, you were born in San Francisco, California?
July 1911. It would help us to know a little bit about your parents and siblings.
On my mother's side, her father went West after the Civil War. He was in the Union Army. She was born in San Francisco in 1883. I had a lot of relative spread around, and they were quite a mixed group. They were middle class, some in the cities — I came from the city part of the family — some were purveyors to the mines, and some went into farms, fruit farming, vineyards, things like that. My father was an immigrant. He came in his teenage from Germany and got to California about 1905. I have a brother and a sister, both older.
What do they do?
My brother was an accountant. He's retired now in San Francisco, and my sister was a housewife, mother and so forth, not a professional woman at all.
I don't hear any scientific connections in your background.
No. My father had enormous interest in science and, in a different world, undoubtedly would have been a scientist, but his father died when he was quite young, and the family put a great deal of attention on an older brother, which was sort of traditional in Europe. My father had to shift much more for himself. On the other hand, he was the member of a family with most of the solid qualities — you know, determination, industry and so forth. My father had a tremendous amateur interest in science, and, as a matter of fact, knew a great deal. He read Tyndell's lectures, and similar literature for example, and enjoyed discussing the easy-to-understand elements of classical physics with me. That undoubtedly had an enormous effect. I always knew, from childhood on, I'd go to college and be a scientist of some kind; I was not sure what. But I went to a very interesting high school. James Lick, who established the Lick Observatory, that's probably his best known philanthropy. He funded a number of philanthropies, all of which still exist. One was a technical high school which now goes under the name of Lick-Wilmerding. Two schools fused at some stage. They once had a women's school connected with them, but somehow that dropped out of the way. I think the girls no longer liked to go to an affiliated school, and it closed down. There was some excellent people at high school, a physicist named Ralph Britton, who's still living in Palo Alto. He was an exceptional person. He would undoubt- edly have been a professional physicist in a university, but World War I got him into uniform. He lost several crucial years and took this job at Lick. He eventually became head of the institution. There was also a very good chemist and there were pretty good people in mathematics.
Were there any particular incidents that stand out in your memory, for example, some particular experiment that you took part in or some particular book that you may have read in that period?
Well, we used the Millikan series. They were a series of books for secondary schools written by Robert Millikan. Also the principal of the school was a physicist and a pretty good one, in classical physics. He had written a textbook. His name was George Merrill. So it was an unusual environment, somewhat reminiscent of what one hears about some of the great high schools in New York City.
Like Bronx Science.
Yes. I got admitted to Stanford, and that was a very critical period.
I would like to ask you one more question about your high school. Was there anyone else in your class who went on to become a distinguished scientist, anyone in your generation?
That was a period when only about 10 percent of the high school graduates went on to a real university or college. One of my classmates is a chemist. He went to Berkeley, and we met occasionally, but he got into private consulting. I met him a couple of years ago in San Fran- cisco, but he was very much retired then.
That also was a period in which radio, ham radio —
We were all ham radio operators, yes. It began with crystal sets and then went on.
Why did you choose Stanford?
Convenience and quality. It was an easy trip, 32 miles from my home. My father was a businessman, middle class. Some of my mother's relatives were quite well off, did very well. My father had an excel- lent business and as a matter of fact, I was lucky because he could afford to finance me during the first year of graduate work at Princeton, at a time when I didn't have any kind of fellowship.
I see. And what was his business at that time?
He was in the baking business.
So he supported you and you lived at home?
No, I lived at Stanford.
You lived at Stanford but would visit frequently.
You entered about 1928 then?
Yes. I entered in January of '29. I was in the class of '32, but Stanford had a quarter system, and I entered in the second rather than the first quarter.
And I gather that you took a math program.
Why did you decide to do that?
The mathematics department was the most disciplined. You know, it had a secretary who registered you. The physics department which was run by a very good physicist, a member of the Academy, quite a re- markable fellow, David Webster was a little bit catch as can catch. Stanford was an extraordinarily open institution then. You could do almost anything you wanted as long as you didn't flunk out. And al- though I knew I wanted to go into some form of physics, it was easier to go through in mathematics. I had a good program. I felt at home there. It had a good li- brary, where you could work. But I took a great many physics courses.
Who were some of your teachers besides David Webster and what did you learn from him? He was an X-ray person, wasn't he?
What was he teaching at that time?
He taught the general physics courses. Then there was P.A. Ross. Ross invented a system of X-ray filters. They were once famous. I don't know whether they still are. They're called the Ross filters and are used to get essentially single line spectra. Paul Kirkpatrick came into the university somewhere along there. He was also an X-ray man. One of my close older friends and teachers was Bill Hansen, who invented the Klystron. Stanford also attracted a number of people who would come for a quarter or two quarters. They had some remarkable people. Ed Condon came one summer, and I met him.
You mentioned he gave some very interesting courses. A seminar on modern physics?
Yes, this was my introduction, so to speak, to modern physics.
I gathered from that that there was relatively little modern physics at Stanford before then, although it was fairly late; this was almost 1930.
They did a good deal of research, and Hansen gave a course on quantum mechanics, which I took, say, as a junior. It was clear and explicit enough so that one had little difficulty in following it. Webster had been one of the people who obtained a value of Planck's constant from the X-ray edge, the upper edge, by changing the voltage; he had done work of that kind as early as, let's say, 1916 or '17. So these people were all familiar with quantum theory, with the Bohr theory of the atom. People talked about the wave equation as though it were a believable thing in physics. So the mood and atmosphere, though somewhat erratic, was pretty solid. There was plenty to absorb for anyone who wanted to reach out.
Was there anyone there in the new generation of people who became familiar with quantum mechanics in the early twenties?
Hansen. Yes. Hansen was about three years older than I. He was pretty conversant with things. We had Kramers as a lecturer. Richtinyen, Karl Darrow, who was a very elegant lecturer. Not a great research man, but an elegant lec- turer.
He had a talent for summarizing the latest developments and presenting them in an interesting way.
You also mentioned Harald Bohr.
Yes, he was there in mathematics for a couple of quarters.
I see. Did he actually give some courses?
Kramers just came as a lecturer?
Kramers probably stayed a month and gave a series of lectures.
Do you remember what the lectures were on?
They were on the correspondence principle, which was something he had been deeply involved in using the Bohr Theory.
The famous Kramers-Heisenberg work, which led right into the matrix approach to quantum mechanics?
Was Kramers a good lecturer, by the way?
Yes. He was an excellent lecturer.
Was Gerald Pearson one of your classmates?
I never knew him then. I met him later at the Bell Labs.
I was under the impression he was at Stanford about that time.
Could well be. We may not have crossed paths. One of my close friends ended up in physics, but through the civil service route. He was in the laboratory at the Signal Corps. We saw a good deal of one another. He lives in Highlands, New Jersey.
What's his name?
Alex de Bretteville. His brother was head of the California Bank for a number of years. He came of a rather aristocratic San Francisco family.
You mentioned that you were reading Brillouin and Ewald among other things as an undergraduate. Were these books part of the courses that you were taking or were they just something you read in order to deepen your experience?
That's right. Every graduate school at that time required French and German reading knowledge. As a matter of fact, an awful lot of the good literature was published in those two languages, before Europe got upset so much.
Then you went to Cal Tech for part of 1930, at Condon's suggestion, and then to Princeton. At Cal Tech, I suppose you heard Ehrenfest?
Yes. Ehrenfest came for a quarter.
What did he speak about?
Quantum thermodynamics. He talked about black body radiation, entropy, things of that kind.
Was that of interest to you?
Yes. You know how it is. As an undergraduate, some of it was over my head. On the other hand, one picked up enough to make it well worth the time. And then he was a very dynamic lecturer who rushed around the room, grimaced, waved his hands, and so forth. It was a lot of fun.
A lot of fun just being there.
Now, some of the other people at Cal Tech then were Houston...
Houston, and Epstein.
Yes, Pauling, then as a very young man, gave a course in quantum chemistry.
I see. Did you take that?
I sat it on his lectures. He didn't give a formal course. It was a seminar course, done in a very informal manner. There was a lot of exchange between him and the people in the class. Cal Tech was quite a good center for physical chemistry. There must have been 30 people in the seminar.
The number of good people who were there at that time is quite amazing.
That's right. Yes.
Shockley was there also, as a student, wasn't he?
Yes, that's where I first came to know him reasonably well. I had actually met Bill earlier at Stanford. His mother was a good friend of the Rosses, and they used to come to Palo Alto for visits. I met him, but it was a very transient thing. One thing to emphasize is that the physics department at Stanford was so small that it was almost a family.
This is at Stanford?
At Stanford. I first met Bill there, and then we were in Houston's class. I guess it was just classical mechanics, upper graduate level mechanics.
I guess Dean Wooldridge was around there then.
Yes. I don't remember him then. I met him later at the Bell Labs.
Then you went right on to Princeton from Cal Tech. Is that right?
No, I went back to Stanford. Most of the students at Cal Tech lived at home, and it was pretty dull. I had to go out and rent a room and so forth. Everybody left the campus about two in the afternoon. So eventually I went back to Stanford.
Where life was more interesting?
More interesting, much more lively.
Is there anything else that we need to say about the years before you arrived in Princeton in January 1932?
I think I've pretty well covered the main things. Incidentally, Webster was a great help in my getting into Princeton, because the western schools weren't regarded very highly on the eastern seaboard at that time, but he was a good friend of the dean of the graduate school at Princeton.
Who was that?
His name was Trowbridge. He was a physicist and a good one. He'd written several textbooks, was a good person, and I am certain his friendship with Webster was an important link in getting in. As I say, the first period I was at Princeton, I had to pay my own way because I came in January. Moreover the chance of getting a fellow- ship was small in the first place. Most of the students, with a few exceptions, at least started there paying their own way. This explains perhaps why the graduate school was as small as it was. Because it was remarkable considering the quality — something under 150 students in the whole university.
Tell me a little more about the environment as you perceived it, coming from Stanford, arriving at Princeton and the East Coast.
Well, you know, you had to get familiar with all the cycles of weather, quite different from San Francisco, where things are almost static. Moreover the student costume at Stanford was quite different from Princeton. Judged by present standards, it was normal but at Princeton you were expected to wear a tie all the time or be ostra- cized. But these were easy things to adjust to.
What about the relationship to senior people, some of the senior people who were around at that time, and the size of classes?
Classes were very small. Twelve people in a typical class. Might have been more at a big lecture if someone special came, but normally classes were very small. I knew Condon from the start. The faculty were easy to get to know, although some of them were quite formal. You didn't see them socially, but because of the small size, there was a family atmosphere. One of the excellent teachers was Lou Turner. He didn't stay at Princeton. After World War II he was head of the physics department at, I think, the University of Iowa and then ended up at Argonne Laboratory. Excellent lecturer.
What did he teach?
He gave a course on a mixture of things to do with modern physics, quantum physics. As was mentioned, when we were with Eugene Wigner, he (Wigner) gave a course in solid state physics.
Did you take that immediately on arrival?
No. I met him the day he left to go back to Europe. He was on a half-time appointment. He and John von Neumann shared one professor- ship.
They were at Princeton at the same time, I gather?
Generally speaking they went there during the same semester.
I'd heard that the offer was designed that way so that they could speak to each other.
Well, they really wanted to get von Neumann. He was the big fish for the mathematics people. They had a professorship which they wanted him to have, but his condition was that he would come only half time, and he wanted the other half for Eugene to have someone to share experiences with and what not. Actually they were very different kinds of people. Eugene was not a highly social person, worked almost con- tinuously at his research, except when he'd go for a walk with his students; whereas von Neumann had an almost garrulous social life. He had a Hungarian wife.
They separated somewhere along the line; she has been at Brookhaven for a number of years. I don't know whether she still has that position, but she was a kind of general manager at Brook- haven. She married one of the graduate students at Princeton, Horner Kuper. But John was always buzzing about in fast cars and had a very large circle of friends, New York City and so forth. So their contact was based on the fact that first, they had to an extent grown up together in Budapest and second had similar experiences in Germany. To that extent, they were sort of intellectual companions.
I understand from some of Wigner's other interviews that he was very lonely at Princeton for a number of years.
I think some of that came out in our conversation. He never felt secure there.
And rightly so.
Yes, rightly so. It's hard to know. Princeton was a very staid, conventional place. Einstein once said, "People here achieve altitude by walking on stilts," referring to the population he found when he ar- rived in 1934. And that to a degree was true. Social factors were very, very important in the community of the faculty. And then, they didn't give Eugene tenure. It's unbelievable in retrospect, but, for one thing, the institution was completely paralyzed by the Depression. That one opening was perhaps the only opening in the department for five or six years. People like Condon and others who came as associate professors never had a change in rank and saw no prospect as long as the Depression lasted. So it was a strange time, judged by what happened after 1940.
What about some of the seminars, colloquia, informal teas, the ways of meeting people and learning physics informally outside of courses? You mentioned that there was a colloquium at which you spoke on Pohl's work on X centers and also on the Meisner effect. Could you tell me a little bit more about this colloquium or any other similar interactions?
Well, the physics department was in Palmer Lab, which was con- nected with Fine Hall. At Fine Hall every day at 4:30, everyone who could walk or go on crutches met in what was called the social room and spent about 20 minutes to a half hour talking. Then there were mathematics seminars — colloquia — and the physics department had its weekly colloquium. The number of people available was sufficiently small that the students often gave seminar talks. That explains why I was allowed to speak to the great faculty.
Do you remember some of the people in the audience when you spoke?
Well, on that occasion, I remember Dirac appeared.
Yes. At another colloquium talk I gave — I think it was on the work Eugene and I had done — Schroedinger was present. I guess that could happen these days, in the right seminar. The big difference was that everyone in the physics department came to that seminar, whereas now you'd have much more breakdown into selected groups because of the size.
A wonderful way to learn how to behave like a senior physicist to present work to them!
Things weren't that different at Illinois when I first went there in the late forties.
Were students also giving seminars?
Students would speak at the colloquium if they had something to say, yes.
I see. Who chose the subjects of the colloquium talks? Did you choose to speak on Pohl's work yourself? Had you started reading about it?
I think someone who was in charge of the colloquium asked if I would try to give a summarizing talk on this.
On that particular subject.
I only know of those two.
Perhaps you gave others?
Those are the two I remember most vividly.
They were both on solid state subjects, so by then you must have been recognized as someone who was definitely interested in solid state.
Well, that's an interesting thing. As you gather, Condon had been of much help in getting me established there. He had discovered the Franck-Condon principle when still a graduate student and had a deep interest in atomic and molecular problems. He had a student Shortley; they wrote a book together, Condon arid Shortley, a very famous book. And I helped them a little in connection with reading manuscript and that sort of thing. As a matter of fact, I think I'm probably mentioned in the preface. When Condon got deeply involved in the final publishing of the book, he didn't want to be distracted. And we had both agreed having done a little work together, that there was a good chance that something would open up in solid state, applications of quantum mechanics to solid systems.
This was around 1932?
'32, yes. And as a result, he brought Wigner and me together. Condon said, "Why don't you take Seitz off my hands so I can get on with the book?" We sort of agreed that we'd see if there was something in the solid state area. And that's when Eugene said, "Well, I have an idea. I don't know whether we can do anything with it but let's try."
And that was the work on sodium.
That's how we got started on sodium.
Before we move to that, which we discussed on Saturday, with Wigner, I have just a few more questions. One has to do with Clarence Zener, who I gather was there for a while and worked on superconductivity before going over to Bristol in 1932. Was there an overlap?
Yes. Clarence is a very interesting person, still very active. He's associated with Carnegie-Mellon University at the present time.
I wrote to him to ask if he would be willing to be inter- viewed. Was it you who said that he was a little bit reluctant?
Yes. I tried to get him involved early on, but he said he doesn't believe in this kind of thing.
I hope he will agree to be interviewed.
I think it would be wonderful. He's a very creative person. He was a graduate of Stanford about five years older than I. We had that in common. He was a National Research Fellow at Princton, I believe, but he had spect a year in England, perhaps on an international fellow- ship.
I see. Is he a little bit older than you?
About five years, roughly, could be four, but something like that. He met his wife in England. They were living in Princeton and they were there about two years. I saw a good deal of them. We'd talk about problems. Then, as I recall, he went back to Europe for a brief stay, then came back to the Institute for Advanced Study, where we held a sequence of jobs. Later on he was at City College for a period. It would be very interesting to interview him.
Now, he was already working on superconductivity in '32. What was he trying to understand — the Meisner effect had not been...
No, that came a little later. No, he was trying to understand the super current, and had the view that in some way the electrons got coupled to lattice vibrations and were brought along. Don't misunder- stand me. He had an enormous amount of intuition about what the in- gredients of the problem were, but didn't have anything like the tools necessary to tackle it.
Certainly superconductivity was considered one of the unsolved problems of that time.
Many papers appeared.
Many papers appeared on that. I remember particularly Peierls' review at that period. And they made statements such as, "now most of the problems look like they've been solved with the ex- caption of superconductivity."
Yes. And Bloch has the view that the theory of superconductivity was a contradiction in terms, because the state should not be stable. He said one of his most pleasant pastimes was disproving theories of super- conductivity as they came along. Of course, the point is that once it was recognized, as Bardeen and company did, that it was a highly coopera- tive thing. You realize that Bloch was in principle right, but the time to achieve equilibrium could be indefinitely long.
Do you remember some other work on solid state that Zener discussed with you while he was at Princeton in this period?
I think he devoted most of his time to superconductivity. One could see what else he published at that time.
Yes. And of course I'll do that whether or not I interview him.
I think he'll let himself be interviewed.
Now, what is there to say about your first paper on the Lorenz double diffraction irregular
It's pretty awful, but —
What brought you to be interested in this problem? And was this your first research problem having to do with crystals?
Yes. Condon was teaching a course on optics, from a book by Born. Was it Born? No, it was Frenkel. We plowed through it. It was on crystal optics. And we had the thought that perhaps if one went to short enough wave length, you would get diffraction effects in cubic crystals. We provided a kind of formalistic approach to the problem but never carried out it in a really quantitative way. We did our best.
I notice there's some use of group theory in the paper.
Yes. I was loaded with groups at that stage.
How did you get started on the group theory work?
As I mentioned the other day, Wigner's book had appeared and was available. I thought I ought to know about it, so I bought a copy and went through it. It was quite evident that the group techniques were very very powerful, because many of the characteristics of spectra could be classified entirely in terms of their group properties. It was very impressive.
By this time was group theory widely accepted?
It wasn't part of the conventional discipline in most places, so it took on slowly. As a matter of fact, I don't think group theory became widely popular until after World War II, when a whole new genera- tion came along. Perhaps the thing that made it an accepted as part of the discipline was the sequence of papers of Eugene's in which he handled nuclear structure with the use of group theory, isotopic number and so forth, and showed that all of those things could be fitted into formal group designation. The generation that grew up with that as a base then went on to do all the things in particle physics in which they used a group framework.
Now, you developed a scheme for reducing the groups and using the results to explore the discontinuities of the energy of the electron waves at the Brillouin zones in metals, where the energy was regarded as a function of the wave number. How did you get onto that particular problem? I gather you started that while you were still with Condon and continued that while you were working with Wigner. And then you must have worked both on the group theory and on the Wigner-Seitz method at the same time?
That's right. The life there was such that you had little to do but research. That was a very exciting period.
How did you happen to choose that particular problem? Did you choose it yourself or did somebody suggest it.
If you mean the reducing the spacegroups, that was my own idea. It was part of the continuous interest in application of Group theory.
Did you have crystals in mind at the time you started it?
Yes. As a matter of fact, in a paper I used as a thesis, I developed a matrix approach to the space groups, a sequence of papers that was published in the Zeitschrift fur Crystallographie.
And then there's also one in the ANNALS OF MATHEMATICS.
These papers are very interesting and everybody refers to them, at least in the early days.
In the early days. Yes.
Let's see, you presented it in four parts. First you derive the 32 macroscopic groups, and present them in matrix represenation, and then you work on the microscopic theory and derive the 14 Bravais translation groups and place them into the development of the space groups. Then you go on and work on the theory of the operator ism and derivation of the space groups using this formalism.
Who did you talk to about this?
Pretty much alone. Wigner wasn't terribly interested in this, you know. He said that stuff is pretty well known, as it was true. There wasn't a high level of originality. It was more an approach. On the other hand, it was enormously helpful to me, in connection with the next step, which was (looking at papers) this.
The reduction of space groups.
Reduction, yes. And in fact, in that sequence of papers which Eugene had with Smoluchowski — you know, Bouckaert, Smoluchowski and Wigner — the ideas in here provided the groundwork. And then I used the ideas in another form in connection with the work that Ewing and I did at Rochester on lithium hydride and lithium fluoride
I'm trying to put myself into the framework of a student at Princeton now. Is this something that you spent most of your time working on in those years?
In streaks. You know, I'd spend a couple of months.
But you were working in a vacuum, pretty much?
How did you know whether you were getting anywhere?
Well, whether it made sense to me when I was through. I think — it's hard to say — today it probably would have been published in some book form, rather than in a journal. But Professor Niggli who was the editor of the series was fairly generous.
I noticed that you not only thank Condon here, but Linus Pauling. What role did Pauling play in this work?
Well, I spent a month or so in the summer of '33 in Pasadena, and I had been working on this and talked to Pauling about it.
And he was interested?
He was interested, but in that way that people are with students.
What about the relationship with the Slater group? Slater writes in his book that he felt with his determinational approach to many-electron problem he had slain the Gruppenpenst, but this work of yours was after that. Was there must interest still?
Slater never cultivated group theory as an approach. I think history has demonstrated that that was probably a mistake, because you had to deal with much more clumsy representations of things — unless you had an excellent intuition. Group techniques let you build up wave functions that you know will have the same energy, handle the degeneracy much more easily.
Right. Herman Weyl must have arrived at Princeton while you were working on it.
Yes. It was of absolutely no interest to him.
No. He was a much more kindly man than people give him credit for, but this didn’t show in his everyday affairs, He was a very single-minded person. As a matter of fact, I met him again years later when we were in Pittsburgh, by which time he’d mellowed a good deal. By that time I knew his son, Joachim, known by everyone as Joe, and found Herman Weyl a far more approachable person than he had been in these years.
While we’re talking about other people, before we get to the next paper, Einstein must also have arrived while you were working on this.
Did you interact with him at all?
No, but he was a commonplace figure in all colloquia and so forth. Even with the addition of the group who later formed the Institute, the community of physicists and mathematicians was still fairly tiny by present—day standards.
Would you sometimes run into him at coffee?
Yes, He was just there, another notable person, Yes. He also was of course quite a figure in Princeton, wandering around the streets smoking his pipe.
Some of the younger people included Hillard B. Huntington, whom you did quite a lot of work with.
Yes, Hill got his degree at Princeton, but actually did his thesis with me at Penn.
Tell me a bit more about him. Is he someone I should try to interview?
Yes, by all means, We’re contemporaries; I think he was in the class of ‘32 at Princeton, didn’t know what he wanted to do, and got a job in a secondary school, teaching, and then decided to go back to Princeton for graduate work. So we met again. By 1940, he was ready to work on a thesis, and we worked together at Penn.
We’ll come to that. And then, your interactions with the chemistry department included Hugh Taylor and Henry Eyring, who had worked with Wigner and Polanyi in Berlin.
Polanyi was interested in rate processes in chemical reactions, and that then played a role in some of your later work.
That’s right. Between us, the real ideas in that famous paper, Eyring, Polanyi and Wigner were Eugene’s. You just know it when you know his style. But Polanyi was interested in rate processes, and Eyring was some kind of international fellow. Eyring recognized however that in the contents of that paper there lay material that could be generalized. He wrote a paper which appeared, I guess, in 1932, which represented a generalization of the techniques of determining rate processes. And then he started out, and it was about a paper a day. No part of chemistry was left untouched by the Eyring school. I saw a good deal of them. He was very imaginative. Eyring is still alive and active.
Where is he now?
He’s at University of Utah. He’s a Mormon. As a matter of fact he grew up in Mexico. Polygamy was outlawed in the United States, and his father and several wives all moved to Mexico, and Henry grew up there. The thing that took him away from Princeton was the Church which asked if he would return to Utah. And he did. He’s still very active. Every once in a while I see a paper by him in the PROCEEDINGS of the National Academy.
You started doing some work with his student Albert Sherman.
This is work on the symmetric states of atomic configuration.
There’s a lot of group theory in that paper.
Well, the people in Eyring’s group used the Slater approach, and it was very, very cumbersome. What A1 and I were able to show is that the ground state, which is the one they were always after, could be constructed very easily in a case where it had any symmetry at all.
This paper appeared after the Wigner-Seitz paper, the first one, but it reads as though the work was done before, Is that correct?
A1 was a San Franciscan, He went to Berkeley and I to Stanford, but we used to meet in the summer time in San Francisco, and this —I don’t know what’s the date on it — but it was probably 1933.
Yes, it appeared January ‘34 so the work was done in ‘33.
Well, we worked on it that summer.
This was published remarkably quickly, October to January.
The JOURNAL was new then — what is it, Volume 2 — so it was just getting started and I think they were anxious to have papers of this kind. As a matter of fact, A1 and I went to Pasadena together to work with Pauling during the same summer and it was in that period that we did this.
So that’s when you did it — I was trying to figure out how you got together.
He had a twin brother, identical twin brother. A1 died very early of a brain tumor, 1939 or ‘40, But we had a lot of fun together, enjoyed working.
You thank Eyring, Frost, Turkevich, and Van Vleck for discussions. Now, what role did they play?
I think we sent a copy of the manuscript to Van, who was amazed. He said, “It’s readable.” He was always afraid of group theory. And the other people were friends at Princeton.
It was sort of a courtesy.
We agreed we’d work with an alkali metal, because they’re the simplest, and we discovered in the literature that someone had worked out an atomic field.
Were you looking for that specifically, or did you just come across it? Was it a well-known paper? Of course, it was in a reputable journal, it was in the Zeitschrift fuer Physik.
That’s right. I think we went through the literature, or I went through it or Eugene went through it, and found a sequence of papers. One was by a Japanese named Sugiura who had used this field.
Had used it?
Yes, for atomic purposes. And I don’t know whether he’s mentioned.
I don’t see his name.
But in any case, I think we got the lead on the field from the Japanese paper that appeared in the Zeitschrift Fuer Phsik and then located the field and decided it was a good place to start.
So Wigner had had this idea and was really looking for an opportunity?
Yes, He decided that the reasons metals cohered was that the wave functions were probably smoother than atomic wave functions An atomic wave function is under the constraint, that it has to go to zero at large distances, whereas in a metal it doesn’t. It was a qualitative notion and we started out to see if we could do something that was rough and ready that would indicate this.
How did you respond? Do you remember the first time he told you about this idea?
We had a meeting. It lasted 40 minutes. Then I probably got to work and started shuffling through the literature to see if we could find anything, and then we shuffled together for a while.
It was a very close collaboration, wasn’t it?
Yes, I was his first student and at that time his only student, so it was a fortunate relationship for me and he regarded it as a good opportunity to learn a little about Americans, whom he then regarded as an odd bunch.
So then you went to the literature, You came across Sugiura’s paper and learned about the Prokofjew potential. Had you already read some of the work that this is based on?
Already in connection with Wigner’s course perhaps?
No, you just read the literature.
So at that time, you were interested in these problems.
And then you sat down, and you saw the problem.
We ran into a sort of impasse, and finally worked our way out of it.
What was the impasse?
Well, it was a question of getting decent wave functions, At first, we tried to take the atomic wave functions and remap them, more or less by hand, in order to get wave functions that satisfied the right boundary conditions. It turned out that the effect we were after sort of slipped through the seive. And finally we had the thought of carrying out a straightforward numerical integration of the wave function, using the field that we’ve talked about, right up to the boundary. From that point on it caught on, because that gave us a precise energy going with that field for a wave function which satisfied the right boundary condition. It sounds simple now, but at the time it was quite a struggle.
Let’s see, the calculation of the wave function took about two afternoons?
And five wave functions were calculated on the whole, giving the ten points of the figure.
Today, you would put the thing in a computer and press the button and you’d have reams and reams. But you know, it was done point by point with an old Monroe calculator that rattled and banged.
While you were working on the first paper, did you already have the idea of going on to a Hartree-Fock calculation later?
Yes. We now had a pretty good idea what the wave functions looked like, and that meant we could go on and do other things. To put it simply, take the Slater determinant and calculate the energy.
Now, the big issue in the second paper is putting in the correlations.
Yes, and that was Eugene’s mastery.
Basically going from equation 21 to 22?
Yes. Unless one introduced correlations, one was shy of binding energy. You had to take into account the actual electron repulsion to get anywhere near the right answer.
Why did you not publish the third paper in the series with Eugene Wigner?
Because that was Eugene’s work.
I see. And in this particular paper, was this section on the correlations also his?
That’s his; yours is the earlier part?
Yes, the earlier part. We got working together in the fall of ‘32, and before he left for Europe to pick up his European appointment, Hitler came into power. By the time he got back to Europe, he had been dismissed, and so he spent the period from let’s say the end of February ‘33 until the next autumn, when he returned to Princeton, at home in Budapest.
The dismissal took place in March?
Yes. He never really tried to go back. He knew he would be dismissed. We then corresponded across the Atlantic, initially on the first part. And then he started working on correlation energy, trying to get an approximation for it. Many people have tried to improve on it by the techniques he used, including me — you know, get higher approximation — but without success. But then in the post-World War II period, when people got much more familiar with multi-body problems, they managed to handle these things in much more sophisticated ways.
You’re talking about the contribution of Brueckner and Gell-Mann in getting the log term?
The mathematical machinery just wasn’t available earlier.
I guess one can say that this calculation of the correlation isn’t really correct, but showed the way; it opened the problem.
That’s right. It’s quantitatively pretty good, but it isn't very elegant.
It got people interested. I’m looking forward to finding out how Gell-Mann, Brueckner, other people picked it up.
The concept of correlation energy then got absorbed into the whole of physics. It was recognized that it’s a phenomenon that occurs in nuclei as well. That is, the proton repulsion is an important constituent in determining the energy of nuclei, so the thing permeated many-particle physics.
I was interested in learning on Saturday that just at the time that Wigner was having such problems with his position, you had four job offers.
Well, they were at a very different level. He was looking for a lifetime tenured job, and I was just looking for a job.
I see. What were the job offers then? Where did they come from?
Oh, I got offered a job in the mathematics department at Cornell. These were instructorships. One at Indiana, one at Rochester, which I took. I was also offered a position in the Society of Fellows at Harvard; I guess that still exists. But it was not designed for a married student, and Betty and I got married just as I finished graduate work, so I turned that down.
I see. Did you meet Betty at Princeton?
She was at Bryn Mawr. I went there once to give a colloquium and we met.
I understand she was a physicist also?
That’s right. She was always torn between physics and music, but became a graduate student, had a year at Cornell and then Richtmyer heard that there was an appointment for an assistant at Bryn Mawr and recommended she take it.
So Betty was at Bryn Mawr as a graduate student with a teaching assistantship in physics.
That’s right. It was about an hour away.
At this time, this is now early thirties, 34 or so, where else in America — besides the group at Princeton, the group around Slater and perhaps a small group around Van Vleck — was there interest in theoretical problems of this sort, having to do with solids, in the US? Or were those I just mentioned the main centers?
Those were the main centers, I’m afraid.
Would you also include the Van Vleck center?
Oh yes. Van was very much a part of the family and had a great interest in metals, ionic crystals. And we all knew one another, on a kind of first-name basis. Van was tremendously interested in young people.
Was this a period when you were already spending summers away in Michigan, Wisconsin? Or did that come later?
Usually on the way West, we’d stop off at either Michigan or, one summer, Wisconsin.
When you say “we” are you including Betty?
No, this was before we were married. Usually a group would go in a car. I remember that Bill Hansen, who’d been at MIT for a year, Shockley and I drove West, and Bill stopped off at Michigan. We left him there, and then Bill and I went on, I think, to Salt Lake City, where I grabbed a train and he went to Los Angeles.
When you stopped off at Michigan and the other centers, did you participate for a while in the activities?
That’s right. We’d stay a few days — see what was going on, who was there.
So by then you were pretty good friends with Shockley.
Yes. We had, as I say, met at Cal Tech and then he started work with Slater, and because of the interest in driving to California together, we got to know each other quite well.
Did you do any talking about solid state physics in the car?
He was a little younger, or in any case behind you in graduate school.
I think we were almost the same age, but he, for some reason, needed money more than I did, and took a rather heavy job at MIT, heavy teaching job, so that he was slowed down a bit in getting under way in research; whereas at Princeton, no one at the graduate level did any teaching. You either paid your own way or you got a research assistantship. It made an enormous difference in the number of hours you had to do research. Bill probably had the equivalent of 12 hours, contact hours, of teaching or something of that kind, for a couple of years.
From ‘34 to ‘35, you were a Proctor Fellow at Princeton.
Could you tell me more about what a Proctor Fellow did in those days?
Well, the Proctor family, of the Proctor and Gamble soap fame, gave Princeton some money for some rather super graduate fellowships, about six of them, I think. And I was awarded one, which was rather nice. By present standards it would pay, $6000, something like that. It was fine, first rate. Now, the stipend hasn’t changed from what it was in my day so it’s no longer a very attractive thing, but it was quite super then.
Did you apply for this fellowship or was it just simply awarded?
No, I think they were awarded by a department. You know, a department would get behind a candidate and present it to a committee. I suspect Condon’s fine hand was involved.
The next piece of work was done with Robert Brattain and R. Bowling Barnes.
Yes, that’s a funny piece of work, and I don’t know where it stands. They observed all the fine structure in transmission, infra-red transmission of thin layers of crystals, the alkali halides. And I tried to explain that in terms of higher harmonies, because it was temperature dependent, strongly temperature dependent. It isn’t a field I’ve followed, but someone told me they thought the effect was a polycrystalline effect, and that when people really did the experiments properly, with single crystal sheets, they did not get it. I don’t know. But at least I made an attempt at an explanation, a very elegant piece of work.
This seems to have been your first chance to work closely with experimentalists.
I gather you must have enjoyed it, because you went on.
It was a lot of fun. Every day you got different experimental results. This was Walter Brattain’s brother.
Yes, I’ve run across him before.
He ended up working for Shell Oil out in Emoryville, and I guess is retired. Very different, known as Breezy to the other students, in contrast with his brother, who is much more staid.
You finished this work after you got to the University of Rochester — or did you write it up at that time?
I think so.
What was of interest to me about that paper is that it’s based on a rather thorough understanding of the Born and von Karman classical theory of the crystal structure and of the group theoretical approach to crystals.
It must have been a great joy to put to use all that machinery!
Yes, I was indefatigable.
— whether or not the experiment was right. Let’s discuss the move to Rochester. Why did you choose that one among the choices you had?
Well, first it was near enough the haunts I knew. I guess if I’d been offered a job in California I would have gone in a jiffy, but jobs were very rare. It was in a part of the East I knew. It was a good job, and DuBridge was starting a new department in rather plush circumstances. Eastman had left a large fortune to the university so it was building a new campus. There were plenty of jobs.
You were by then married.
So Betty came along. Did she get a job there too?
No, Betty and I decided to write a book, and she spent a lot of her time making sure that the text made sense and so forth. In retrospect it should have been published as a joint effort.
That’s your big famous book. It’s now the mid—thirties, ‘35. At this point did it look as though the University of Rochester was going to become a center for solid state physics?
It certainly looked as though it could. DuBridge, who had been interested in the photoelectric effect and had written a book with Hughes, decided to become interested in nuclear physics. But he kept a small group going in the old problems, and that group of graduate students kept churning out papers until DuBridge went off to war to become head of the Radiation Lab. There were several good friends who emerged. One is Bob Naurer at Illinois. He was a graduate student. We got to know each other.
He was a graduate student. Under whom did he work?
And Leroy Apker who eventually went to General Electric Labs. We all became very fast friends.
Did Naurer or Apker have anything to do with the book you were starting to write, with Betty’s help?
No, they were graduate students and sat in on the lecture courses.
The first paper that you worked on there was this one with Ewing on the electronic constitution of crystals, lithium fluoride and also lithium hydride. Now, this is essentially an extension of the Wigner-Seitz work.
That’s right, two ionic crystals.
Two ionic crystals. And you attempt to find a self-consistent solution of the Hartree-Fock system.
And did a much better job than I thought we could. We actually seemed to find a reasonably self-consistent system in both cases. Partly luck.
This had never been done before for the ionic crystals.
Were the ionic crystals sort of the second level in difficulty after sodium?
Yes, approaching it by this technique. By treating ions as rigid charged balls, people had been able to do a great deal. But this was a stage more sophisticated than that.
Why did you start with lithium hydride?
Simplicity. Simple ions.
And what role did Shockley play in this? You thank him in the paper.
Oh, we talked about it at meetings and so forth.
Here again you make good use of the group theory.
For getting appropriate wave functions, yes.
Now, you wrote a series of articles for the JOURNAL OF APPLIED PHYSICS with Ralph Johnson. Did these have something to do with the book you were beginning to write with Betty?
In a way, yes. We had already started the book. I spent a summer at General Electric, and Ralph and I decided we’d try to write a popular version of these things because many people were interested in them. Ralph had been a student at MIT under a man who was at that time one of the leading people in electronics, Nottingham, and had a good background. We formed a good team. Ralph stayed at GE; he left during the war to undertake a special mission in England, and then he joined Ramo and Wooldridge to form what eventually became first Ramo—Wooldridge and then TRW.
What was the response to these articles?
They were very popular. We got requests for reprints until they were all gone.
They’re very clear, useful to me in the early stages of writing.
But it put the band theory, so to speak, on the map, in the popular sense.
How did you work out the collaboration? Did you sit together and write, or did one of you write?
I would write a draft and then Johnson would say, “This is pretty awful,” and rewrite it. Then Betty would check us both out.
About this time Betty organized some study sessions at Cornell on solid state aspects of electronics. Could you tell me something about that? I came across that only once before, in an interview I had years ago with Foster Nix before he passed away. And I don’t know where to get information about that.
I think it’s pretty important. Cornell had quite a good physics department that had a combination of interests in thermionics, which was tied to solid state because the thermionic emitters were made of barium oxide. There was also great interest in X—ray work.
There was a group of X—ray people there. Who was there in thermionics?
Well, there was Lloyd Smith who worked in various aspects of electronic theory, materials. And they succeeded in getting Bethe to come. As I remember, I met Bethe there just after he’d arrived. It must have been the summer of ‘35. I was spending that summer at General Electric. My boss was a person called Dushman who was quite an interesting fellow. We remained good friends for the rest of his life. Saul and I and someone else drove to Cornell for a conference on thermionic emission. A lot of people from the Bell Labs came. Joe Becker, who was an associate of Walter Brattain and so forth. Langmuir was there. And Bethe arrived and participated in this, obviously very lucid, and brilliant.
There was a lot of disputation about some experimental results, and Bethe tried to straighten it out. He stayed on at Cornell and beginning in that autumn arranged two kinds of colloquia, one in nuclear physics, which was his primary interest at that stage. And out of it came the Bacherand Bethe series of articles in the REVIEWS OF MODERN PHYSICS. There also was a seminar in solid state. I remember I went to Ithaca a couple of times in that period to give talks.
How often did they meet?
I suspect that they met as a department weekly in each of the two seminars. You know, people didn’t travel much then, unless they were invited to give a colloquium somewhere. I would guess that the solid state seminar went on for several years. But in the meantime nuclear physics was becoming a big thing for Hans. He got interested in stellar evolution and all these problems. Very much the center of things.
Would you have notes of this somewhere?
I doubt it.
There must be someone who’s got a little program. Maybe they have it at Cornell.
That would be your hope.
I’ll have to write to Cornell about it. Let’s chat briefly about the summers of 1935 and ‘36 at GE. What did you do there?
Well, an interesting thing: they pretty much let me do what I wanted. Dushman was my boss. I had been hired, if I can use the term, by Albert Hull, who hoped he could get me to come to the laboratory. Then he turned me over to Dushman who was deeply interested in trying to understand quantum mechanics. We spent a lot of time together, just talking about quantum mechanics, as Saul went through the process of learning it. A remarkable thing. He was well in his fifties and was taking on this rather formidable subject in addition to all his administrative duties.
Were you reading textbooks with him?
Well, he was writing a textbook which actually appeared — I have a copy somewhere — on quantum mechanics. He wrote as a chemist and also to educate himself. Then I got involved in some experiments on arc discharges. They were developing the sodium vapor lamp, and I worked on it. They were also starting their work on crystal fluorescence, fluorescent lights and lamps, and I fussed around with that. There were interesting things going on in the laboratory. They were making materials and discovered their sensitivity to moisture. It was a rather loose organization, and I spent part of my time just meeting people, part talking, doing what I wanted.
It was very different from Princeton or Rochester, because there were people actually working on practical things. It must have been a tremendously different feeling for you.
The people were earning their living at research by paying attention to practical things.
Here, if you made up a theory to describe some phenomenon that they were observing, the gratitude must have been enormous compared to something like that in academia. Or maybe it didn’t happen much in academia?
Yes. What one did was help create a kind of atmosphere. Dushman, as I look back on it, felt fairly alone there, because he had all these interests in electron theory and was almost the only person, Laugmuir had got off to working on his thin films. And one of the really brilliant people, other brilliant people — namely, Hull — was involved in heavy duty thermionic systems. He was helping to design power vacuum tubes and had little interest in the kind of scholarly study of quantum mechanics that Saul had. So we spent a lot of time together.
I had always had the impression of GE as being one of the only places except for Bell — although I considered GE ahead of Bell for a while in its academic orientation — where physicists could come into basic research in an industrial environment. What you’re saying suggests that things were beginning to change by the late thirties. Is that true?
I would say that up until the time Jim Fisk came to the Bell Labs and headed it, it had almost a paramilitary organization. I think organization charts meant more at the Bell Labs than they did at GE. On the other hand, Bell always had a policy of giving a few people complete rein. Davisson I’m sure did just about what he wanted, and there were other people. There was a fellow named Ives. There’s an Ives Medal named after him, He did almost what he wanted.
That’s right. But GE was more informal. Organization charts didn’t mean too much.
Did that stay true throughout the period that you worked there?
It stayed true and was carried on very much that way into the postwar period, and then something radically different occurred in the sixties after Guy Suits retired.
What about the business of allowing Saul time to study quantum mechanics at that time? Was there generally an interest in getting new ideas from books, as there was at Bell Labs in the late thirties? I learned about several study groups there then in which people sat around and read MOTT AND JONES and MOTT AND GURNEY.
At GE, Ralph Johnson and I were the first two people hired in the laboratory since 1929. So there’d been a long period of stagnation.
That was because of the Depression.
The Depression, that’s right. They didn’t let any people go. They may have let one or two go, but it was a frozen situation.
So you and Ralph Johnson were the young people who knew about the quantum theory. Was there any attempt at GE to try to get you to bring the other people up to your level?
Yes. I gave lectures and people came — small groups. They had a very brilliant young fellow — he’s an older generation than I but he was young by the standards of the day — who somehow or other never quite came up to his intrinsic talents, a fellow named Lewi Tonks. You’ve probably never heard of him.
I have heard of him but I don’t remember in what context.
Well, he worked in a number of fields including electric arcs. There were also some very interesting papers on the magnetic properties of materials, a series of papers, SIXTUS and TONKS. Sixtus was a German who worked in the laboratory for a number of years. Lewi got interested in social problems, ran for mayor of Schenectady on the Socialist ticket, things of that kind, and diffused his talents.
Were other people hired at the same time as you and Ralph Johnson or did that come later?
That came later.
You were the young new ones then.
I gather there was an interchange with RCA?
Yes. That’s right. RCA was formed in the late twenties by a patent pool, something which probably would not be allowed today. A number of companies pooled their patents, formed RCA, and then derived certain royalties out of this pool. And General Electric had an agreement that they would trade information in certain fields. One was the field of fluorescence. And Leverenz was the man at RCA, who was making large numbers of fluorescent materials in the laboratory. I think he made a half million in the course of five years. Very good chemist. He was interested in luminescent materials for television tubes, whereas General Electric was interested in them for illumination. He would come to Schenectady and I would frequently go to visit RCA labs, which were then in Camden. So we became good friends and worked together.
The paper that you wrote with Saul Dushman on the quantum theory of valence is rather general. It sounds almost as though you’re trying to introduce the subject to an audience.
Yes. It was published in the JOURNAL OF PHYSICAL CHEMISTRY. I guess Saul had enough weight. It’s a symposium paper. We gave a paper at that meeting in 1937. That’s the first time I met Edward Teller. It was just an attempt to educate the chemists on the wonders of the use of quantum mechanics.
After this or at the same time, you made a definite move into the study of luminescence. You studied for example zinc sulfide.
And then that marvelous set of experimental papers that came out of Gottingen. Pohl had a group that did a lot of work on the thallium—activated alkali halides.
How did you get started on this? Was it the knowledge of those experiments, or was there some interest in GE in making use of these zinc sulfides?
General Electric had decided to go in on a heavy basis to manufacture luminescent lamps, and practically everyone in the Dushman group, plus people in Cleveland where the great lamp works was, was doing research with luminescent materials. I knew of the work of Pohl’s laboratory because of the fact that I kept up with the literature, and pulled it all together into this paper — or maybe there were two, I forget.
Well, I think these two papers here are together. I think they’re published in different places. “An Interpretation of Crystal Luminescence.”
It’s at a somewhat different level.
Somewhat different levels. I was invited to come to the Faraday Society Symposium, but never could get travel expenses paid at that stage for the venture. Life was very different then.
Other problems you were working on at the same time were lattice defects in the silver bromide. Now, was this the beginning of the work on defects?
Pretty much. Yes. I think this was the start.
At this time — this is 1939 — I guess there had been quite a bit of work in Germany and in Britain but not much in the U.S.
Very little, in any systematic way.
Do you remember how you got started on that subject, which became a many many years’ project of yours?
I guess the kickoff was the work on luminescent materials. You know, there are two types. There are those that are intrinsically luminescent and those that depend on defects. And then at this stage, Mott was beginning to get interested in these things, and MOTT AND GURNEY appeared — I forget what year that book was. It may have been later.
It was in the forties.
But in the meantime Mott was publishing papers in the literature on the defect properties.
And you were reading this literature.
Yes. I met Mott, I guess it was in 1938.
At the Pittsburgh session?
The Pittsburgh summer session, yes.
Do you remember what he spoke about?
Mainly about defect properties in crystals, in the alkali halides. And he had done this very beautiful work on the silver halides. Caused a lot of excitement. I remember I went back to Schenectady by way of Rochester with him, where he talked to the colloquium at Kodak.
I see. Tell me more about the Pittsburgh summer school, since that also seems to have been quite pivotal in the history of American solid state physics.
It was run by Elmer Hutchinson.
Was it only one summer?
There were two summers. Betty assures me of that. Both John Slater and Bertram Warren from M.I.T. were leading speakers at the second.
I have a program. Bardeen found a program from 1938 — or maybe that was the only one?
Well, there were two. Hutchinson got money from the local industry. Incidentally, by that time Condon had moved to Westinghouse to head the research laboratory. He went either in ‘36 or ‘37, and he helped Hutchinson organize the thing, get the money from the local community. Westinghouse depended on the University of Pittsburgh for a certain kind of collaborative work, so that there was an excellent relationship, and so Hutch got the money to pull this group together. On the whole the second summer may not have been as grandiose as the summer of ‘38.
Can you tell me how long it lasted?
Probably a month.
Yes, I was probably there two weeks.
So people came for portions.
And there were probably lectures every day.
And time to interact.
So Mott was there, got interested in defects.
I guess some people from Bell Labs. Shockley certainly appeared at some point.
Bardeen went. So that was important. While we’re on summer sessions, I gather you went to the 1938 summer session at Michigan.
Where Kramers spoke on quantum electrodynamics.
Yes. I gave some lectures there.
What did you speak on?
I think I talked on crystal physics. I gave a couple of talks, probably talking about the luminescent materials.
And by this time Zener was back in the neighborhood. He was at CCNY.
Did you have exchanges with him?
Yes, I used to go there and see him. It was a completely odd situation. They didn’t have any laboratory space, but Clarence turned a large closet into a research laboratory and was doing experiments on damping, internal friction. Very remarkable person.
Was CCNY a reputable research school at that time?
It had a number of faculty members who were quite good, many of whom did their research at Columbia. I don’t think they had any significant laboratory space, but there were opportunities to do work elsewhere. The faculty had some quite distinguished names. You know, I could think of about a half a dozen people, if I put my mind to it, who were far from trivial.
Can you think of one or two?
Well, Zemansky, who wrote a famous textbook on thermodynamics, a classic in the country. There were people like Wally Zinn who, I’m pretty sure, was at City College, and did his research at Columbia. Also some of Rabi’s people were at CCNY. Remember, he had this stable of people who did the molecular beam work, and a number of those had jobs at CCNY but would rush up to Columbia to work with him.
I forgot to ask you a question about the work at GE. At Bell there was a lot of work in the thirties on copper oxide, by brattain and others. Was there any similar work at GE?
GE made copper oxide rectifiers, had a very low level of research on them. Westinghouse in turn took them much more seriously and had a small group of people that I came to know very well.
Who was in that group?
The names I remember are Wilson and Rein.
All right, now we’re up to the spring of ‘39. At this point, you moved to Penn.
And that had something to do with the economic recession at the end of ‘37.
Yes. GE went back to either a 4½ or 4 day week, and I was offered a good job at Penn.
I gather that Gaylord Harnwell, the department chairman there, assured you that you could build up a solid state group there. Let’s go over now what the main solid state centers were in the U.S. at the end of the thirties. Princeton is now no longer a major center for solid state, is it?
Not quite true. You know, Eugene returned about 1938. And he still kept a partial interest in this field, an intellectual interest. It is true that he recommended that students who got really seriously interested go to Penn to work with me, Both Huntington and Sampson came from Princeton. I think Sampson actually ended up getting his degree from Penn, but Huntington did his thesis with me and got his degree at Princeton. But it is true that until Princeton formed its engineering department and hired people like Smoluchowski in the fifties, it went to a very low ebb.
Now, Slater’s group continued to be productive throughout this period.
What about Van Vleck’s group?
Van had some very good people. Individuals like Harvey Brooks, as I recall, worked with him. Henry Hurwitz who’s now at General Electric and Malcolm Hebb. Phil Anderson also did.
Oh yes, he worked with Van Vleck.
So Van kept a small group of students going.
Who would be a good person for me to interview to learn more about the Van Vleck group?
Brooks ought to know. Harvey was off at GE for a while working in reactor science but returned to Harvard, I would guess about 1951, and certainly stayed in touch with Van.
What about the Slater group? Is Harry Krutter still around?
I ran into Harry Krutter. I think he’s at RCA or was. We can easily find out in AMERICAN MEN OF SCIENCE.
He’s one of the earliest people. Then there’s somebody named George Koster, who was at M.I.T.
I’m just trying to find one or perhaps two people.
If Krutter is around, he’s a very affable fellow who’d be easy to talk to. He would know those days. I don’t know what you can get out of Shockley. Have you tried?
I tried to interview him a number of years ago about Bell Lab days, and I would say he gave me some information.
Well, Bill turned very sour on the Labs at some point, but I don’t think he was ever sour on Slater and his group.
Well, I’ll get back to Shockley.
See if you can get anything out of him.
He underwent some — well, I guess it occurred in several stages — enormous change in outlook and personality, first in the mid—fifties and then again later on in the sixties, after that automobile accident. Something happened to him then. That’s when he got on the issue of blacks and so forth.
Well, I will certainly try. So we have still the group at Cambridge, and Princeton, now operating at a less intense level than in the earlier period. How about Rochester, is that still a center?
Yes, until DuBridge left to go to the Radiation Lab. He kept a group going. In the postwar period it changed a good deal. DuBridge came back briefly, but then he knew he wasn’t going to stay and went to Cal Tech. The things that went on centered around the Institute of Optics, and some people in the physics department. But Rochester came up after the war again.
I see. How important was the Columbia center?
Almost negligible. There was Quimby’s research which was rather specialized, although he had some good people, including Siegel, (Andrew) Lawson, and Read.
Were there any other groups in academia that were prominent in the period just before the war?
Almost not. A German refugee named George Sachs went to Cleveland, either Western Reserve or Case, and had a lively group around him. When the war came he got involved in ordnance work as a metallurgist at Case, did work under contract, and so sort of moved out of the intellectual circle. There was the infra—red work at Michigan. There was a group working under Harrison Randall at Michigan that did infra—red work on various materials. But it was thin, looked at nationwide.
And that was all experimental?
It was experimental, yes.
Let’s move on then to your move to Penn. Besides you, there was Andy Lawson, who came from Quimby’s group, and then there was Park Miller.
Park Miller from Cal Tech.
These people were younger?
Yes. They were both fresh PhD’s.
Bob’s arrival was somewhat different. He came on one of our NDRC contracts.
He had gone from Rochester to work with von Hippel at M.I.T. That petered out at about the time we were starting work on semiconductors at Penn, and he joined us there as one of the people on the contract. As I say, we had known one another.
And then Hill Huntington was sent up by Wigner from Princeton.
And James Koehler came from Michigan.
Also a fresh PhD?
Yes. Jim came on a fellowship. The Rackham family had left some money to support doctorate and postdoctorate work, and in the competition Jim won a Rackham Postdoctorate Fellowship and decided to work with me. We had met at Michigan.
So that’s how we got started.
And he later joined Cyril Smith at Chicago, didn’t he?
No, that was Andy Lawson.
When Jim left me at Penn, he went to Westinghouse and then joined me at Carnegie Tech, joined the department.
That was the group then that you put together, or did I leave someone out?
No, you have it. I don’t think there’s anyone left out.
Now, did you round up the whole group to start work on certain subjects that you wanted to attack and did the whole group start working on these?
No, we got started before the war. I got pulled into war research on a part—time basis, but Jim Koehler decided he’d become an expert on dislocations and did some very nice work, and Hill worked on ionic crystals. I forget what Lawson began his research on. He started in with Quimby, and duplicated Quimby’s apparatus. And about that time we began to get into war research. Then we worked together on silicon.
What was Quimby working on?
Quimby spent his research time in World War I on quartz crystal oscillators, which were a new thing. When he returned, from, I guess, work with the Signal Corps, he began using quartz crystals to drive other crystals and got interested in elastic constants, internal dissipation and things of this kind. It was a highly specialized technique which allowed you to do a large number of diverse experiments. His Bible was that book of Voigt. All the students had a very thorough indoctrination in that.
I took a course with Quimby when I was a graduate student.
I haven’t seen him for several years. He’s still around.
I tried to give him a call yesterday but I couldn’t reach him. They may be away.
They love boat trips. Edith Quimby is a very good friend, not only of ours but of Betty’s cousin who was in charge of radiation physics at the Bureau of Standards, so we stay in touch through an intermediate these days.
Could you explain how you set up the association with DuPont?
Well, that started in an interesting way. I had published a paper while at GE on the darkening of crystals, and someone in the literature survey team at Dupont ran across it. Pigments people were having a lot of trouble with one of their pigments, so—called chrome yellow, which was widely used then, lead chromite, has since been forbidden because of its lead content. So they asked if I would help them, and I said I would if they would support some research for graduate students at Penn, which they did.
Where was DuPont’s center?
That center was at Newark, New Jersey. They still have a big plant there, and I think all they have left is a test lab. But they had an excellent man, a Mr. Allen, actually Dr. Allan, who had been I think a professor of chemistry somewhere in the Midwest, who appreciated the importance of research in general. We were able to demonstrate — and a couple of theses came out of this for some of the students at Penn — that there was an intrinsic instability. That is, chromium didn’t want to stay in the valence state associated with the yellow color at room temperature and normal oxygen pressure.
How long did this collaboration or interchange with DuPont continue?
Well, another branch of the pigments department, which was near Wilmington, decided that it wanted to explore all possible white pigments that might be competitive with titanium dioxide. When lead oxide was ruled out in the early thirties — it used to give painters painters’ colic; it was poisonous — they moved over to titanium dioxide, which had been developed in Europe for the same health reasons. As a matter of fact they took over some European patents. Having a very strong position, they wanted to be sure that there was nothing else that was going to undercut that. So in Wilmington they started what was essentially a very open research program on the fabrication of an unlimited number of white pigments with a high refractive index.
They had heard from Dr. Allen that I was a person who might be useful, so they invited me down. This turned out to be a very exciting program, because they had probably 30 chemists working on this field. I’d go down once a month and we’d spend a day talking about things that could be done, and I would go through the literature in search of high index compounds. We ended up settling on the thing that would be the most likely candidate, namely silicon carbide, which is normally anything but white. But that’s because of impurities and stoichiometric imbalance. We finally decided that you could not really get it in stoichiometric form in quantity. But in the meantime, they had done an enormous amount of interesting research on compounds.
What sorts of things came out of the research?
Well, as far as their interest, the main thing we proved was that there was no competitor likely for titanium dioxide. That to them was enough to justify the program. But in the meantime we became interested in silicon rectifiers.
When you say “we” you mean Penn?
Our group at Penn.
No. At that time the people were making the rectifiers in a very crude way. They were simply buying metallurgical grade silicon and looking around for hot spots, which was something that went way back in the lore of crystal detectors.
I’ve heard about that.
And knowing what we did about semiconductors and all the other things that had gone on — copper oxide and so forth — it seemed clear to me that if we could get pure silicon and then begin doping it, we’d be well ahead of the game.
What year was that?
Probably 1942, I would guess. Had to be earlier than that. Probably started in ‘41.
Did you know about the similar work that had been done at Bell just before the war by Scaff and Theuer?
I knew Scaff, early on in the war. Once the war effort got under way, and even before we were in it, that is before Pearl Harbor, there was a community formed around the problems of silicon diodes. Bell Labs opened up its activities, I think because it felt that there was much at stake, and that it could learn. We were funded by the OSRD, and I guess Bell, for the most part, spent its own money. But Scaff’s work — with all due credit — was fairly primitive. What he was doing was taking commercial grade silicon and trying to refine it by multiple crystallization, whereas what we did was get DuPont to make O.O.% pure silicon from scratch, which is far purer than anything Scaff had.
Tell me more about what you did.
Well, I talked DuPont into taking on a contract with the Radiation Lab to make pure silicon. Then they became the principal supplier.
To the M.I.T. Rad Lab?
To anyone who went into the business of making rectifiers. RCA was certainly in it, and there was a company near Boston, I forget whether it was Raytheon or not. Sylvania was in it. And it became, in a certain sense, big business. DuPont dropped all that stuff at the end of the war because they’d been accused of being “merchants of death” at the end of World War I. But then the Bell Labs, after it got involved in the transistor, asked them if they’d go back and manufacture silicon, which they did.
Aside from learning how to produce pure enough silicon, learning how to dope it just the right way, what did you learn about the physics of silicon?
Well, we did a lot of experiments, Hall effect measurements. We knew about mobilities. We knew about densities of carriers. We learned about band gaps, what they were. By this time quite a large group had started in. The Radiation Lab decided to farm out programs to a number of places. We were the first outside group of any significance. But then they got Lark-Horovitz into the act.
He worked on germanium.
Yes. That’s right. At the moment I forget to what extent he worked on silicon. Practically all our work was on it. He formed a liaison with Eagle Pitcher who supplied him with germanium. Eagle Pitcher is a producer of zinc lead, and other metals. Germanium appears as an impurity in lead, which they would remove and sell to him in pure form. There was a group at General Electric under Harper Q. North working on germanium. He felt it would in the long run be more promising than silicon. And it certainly played a role.
Yes. What were they doing on germanium, also trying to get it pure?
No, it was easy to purify. There was a well developed chemistry. You could use wet chemical techniques on it.
What were the studies on germanium?
Well, how was it as a rectifier? How would it hold up? What power load could it stand? And things like this. It was quite clear that whatever virtues germanium had, if you could duplicate the chemical quality in silicon, you would have a much more stable product. We fooled around a bit with germanium but more as an oddity. As I recall, I purchased some from a physical chemist at the University of chicago named Warren Johnson, who had made it for some other purposes, as a reagent.
Another thing I was going to ask you — let’s go back for a minute to the summer of 1939. I gather you spent some time at Westinghouse?
That’s right. Ed Condon was there and invited me to spend some time with his group. He had a group of postdoctoral fellows at the laboratory, and he asked if I’d come and discuss their work. They were allowed to do anything they wanted.
At Westinghouse. They were given a research lab and facilities.
I see. What was their main concern?
Well, they were doing various things. I don’t know whether I can think of them all. There was a fellow, Tom Read, with whom I worked later. He had been one of Quimby’s students and he got interested in plastic flow. He proved that some of the dissipation was associated with the dislocations.
Now, at this time dislocation theory was also a very new field, wasn’t it, in the U.S.? It had been discovered in the mid-thirties.
Yes, there were three independent discoveries. One was Orowan.
Right. I’ve written to him. I guess he’s a good subject for me, too.
He would be a good subject. Very talkative. Loves to discuss things. He had some of the same experience that Eugene had. They’re both Hungarians. He passed through Berlin, so they knew each other. He went to England and then came to the United States.
Then there’s Taylor, G.I. Taylor and Polanyi.
Now, what did Read do at Westinghouse?
Well, he was doing experiments using Quimby techniques. We worked together and then wrote some papers together. Roddeson: Did you continue the association with Westinghouse beyond that time?
It was a small thing. I may have gone there a year later for a month.
Read stayed there for a while?
Read went to Frankford Arsenal after several years, and I saw a good deal of him there because I became involved with the group at the arsenal during the war,
I think this is a good place to stop. I think we should pick up at Frankford Arsenal.
 Ergebnisse d. Exact, Naturwissenschaft, 11, 264 (1932)
 Lorentz Double Refraction in the Regular System, E.U. Condon and Fred Seitz, Journal of the Optical Society of America, 22 pp. 393-401 (1932)
 "On the Reduction of Space Groups," Frederick Seitz, Annals of Mathematics 37, pp. 17-28 Jan. 1936
 "On the Electronic Constitution of Crystals; LiF and LiH," 50, pp. 760-77 (1936)
 J. C. Slater, Solid State and Molecular Theory: A Scientific Biography (John Wiley, N.Y. 1975)
 “On the Symmetric States of Atomic Configuration,” F. Seitz and Albert Sherman, Journal of Chemistry Physics, 2 11-19 (1934)
 “On the Constitution of Metallic Sodium,” E. Wigner and F. Seitz, Physical Review, 43, pp. 804–810 (1933) and “On the Constitution of Metallic Sodium, II.” E. Wigner and F, Seitz, Physical Review, 46– pp. 509–524, (1934)
 See interview with Wigner and Seitz by Hoddeson and Baym, 24 Jan, 1981
 On the Constitution of Metallic Sodium II, E. Wigner and F. Seitz, PHYSICAL REVIEW, 46, p. 512 (1934)
 M. Gell-Mann and K. Brueckner, “Correlation Energy of an Electron Gas at High Density,” PHYSICAL REVIEW, 106 (1957), 369–372.
 R, Bowling Barnes, R. Robert Brattain and Frederick Seitz, “On the Structure and Interpretation of the Infrared Absorption Spectra of Crystals,” 48 pp. 582–602 (1935).
 THE MODERN THEORY OF SOLIDS (McGraw-Hill, 1940)
 Douglas H. Ewing and Frederick Seitz, “On the Electronic Constitution of Crystals; LiF and LiH,” PHYSICAL REVIEW, 50, pp. 760–777 (1936).
 Frederick Seitz and R.P. Johnson, “Modern Theory of Solids,” JOURNAL OF APPLIED PHYSICS, Part I, February, 1937, pp. 84–97; Part II, 8 March, 1937, pp. 186–199; Part III, 8, Apr. 1, 1937, pp. 246–260.
 Bethe has same recollection in his interview with me on 29 April 1981. L.H.
 “An Interpretation of Crystal Luminescence,” Frederick Seitz, TRANSACTIONS OF THE FARADAY SOCIETY, 35, pp. 74–85, January 1939.
 Oxford, 1940.
 LEHRBUCH DER KRISTALLPHYSIK