Coherent Raman observations of factor group splittings and lattice vibrations in nanocrystals formed in supersonic expansions

摘要

Coherent antihyphen;Stokes Raman spectra are reported for solid, nanometerhyphen;sized C2H2and CO2aggregates formed in free jet expansions. From comparisons with spectra of equilibrium samples, the clusters are seen to be face centered cubic with a crystalline character indicated by the appearance of vibrational factor group splittings and, for CO2, by the observation of two external lattice librations.