Raman Spectrum of a Single Crystal of Benzene

Abstract

The Raman spectrum of a single crystal of benzene at 140°K has been obtained using an argon ion laser source. The single crystals were oriented with the aid of a polarizing microscope. This technique was found suitable for low temperature work. Despite some cracking of the sample, the polarization was defined well enough to make the assignment of most librational lattice modes certain. The internal vibrations were also investigated, and for ν6, ν9, and ν10 the observed peaks have been assigned to their proper factor group species. The agreement between observed frequencies and those calculated in this laboratory is extremely good for the lattice vibrations, and acceptable for the internal modes.