Low temperature Raman spectrum of rhombic sulfur

Raman spectra of polycrystalline samples of rhombic sulfur have been recorded at 100 and 300 °K, with excitation by the 5145 Å line of an argon ion laser. Spectra of sulfur solutions in carbon disulfide and bromoform were also obtained to aid in assignments. Experimental confirmation is presented of the frequencies of two intramolecular fundamental vibrations, suggested from normal coordinate analysis (one at very low frequency, the other inactive in both Raman and infrared for the free molecule). The spectra are analyzed in terms of the static and correlation crystal field perturbations, and for all except the weakest bands, substantial agreement is obtained. It is concluded that the effects of the two types of interaction are comparable in magnitude, and that a correct analysis must take account of the full symmetry of the unit cell.