Number 340 (Story #2), October 8, 1997 by Phillip F. Schewe and Ben Stein
MOLECULAR HYDROGEN SHOULD BECOME SUPERFLUID if placed on the right surface, say physicists at the University of Illinois (David Ceperley, ceperley@ncsa.uiuc.edu). Superfluids, substances that flow without friction, are few in number: liquid helium-4, special gases of rubidium and sodium atoms (in the form of Bose-Einstein condensates), pairs of helium-3 atoms, and pairs of electrons (which flow through superconductors). The trouble with getting hydrogen molecules (H2) to become superfluid is that they are all too ready to combine with each other into H2 solids. By laying them on a silver substrate and by salting them with a pinch of alkali metal atoms, the H2's should be able to resist the tendency to solidify all the way down to zero temperature. At 1.2 K they would become a superfluid, the Illinois theorists predict. They believe this can be carried out over the next year, after which experimentalists could explore unique hybrid superfluids, such as H2/He-4 mixtures. (M.C. Gordillo and D.M. Ceperley, Physical Review Letters, 13 Oct; figure at Physics News Graphics)
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