STRUCTURE AND SPECTRA OF 3-DIMENSIONAL (H2O)(N) CLUSTERS, N = 8, 9, 10

The vibrational OH stretch spectra have been measured for size-selecte d pure water clusters (H2O)(n), in the size range n = 8-10. Comparison between experimental and calculations suggests that the spectra origi nate from a small number of ''microcrystalline'' structures, based on the cubic octamer. The n = 8 spectra are caused by two isomers of D-2d and S-4 symmetry. The proposed lowest energy nonamer and decamer stru ctures are derived from the octamer by insertion of one and two two-co ordinated molecules, respectively, into the cube edges.