Number 5 (Story #2), October 18, 1990 by Phillip F. Schewe and Ben Stein INDIUM-PHOSPHIDE CLUSTERS ,some containing only six atoms, have optical properties similar to those of InP in bulk form, according to scientists at AT&T Bell Labs. Owing to the fundamental structural differences between a collection of atoms locked in small (perhaps ringlike) clusters in a gaseous state and atoms sitting in a crystal, the absorption spectrum of the clusters should have been much different from that of the bulk material, but was actually very similar: both exhibit a continuum absorption band. The puzzled Bell Labs scientists are studying the effect of cluster size on the resultant spectra. (Physical Review Letters, 22 Oct.; contact Mary Louise Mandich, AT&T Bell Labs, 201-582-3396.)