VIBRATIONAL SPECTRA OF S7Se AND A COMMON FORCE FIELD FOR (34)S8, (32)S8 AND S7Se

Article abstract of DOI:10.1016/0022-2860(82)80007-0

Raman spectra of solid S7Se have been recorded both at room temperature and at low temperatures down to ca. 30 K.Abnormal half-widths of the low-temperature spectra compared with those of S8 indicate that an ordered phase of S7Se does not exist.Simultaneous calculations of a valence force field for (32)S8, (34)S8 and S7Se yielded a refined force field for elemental sulphur along with the force constants of SSe bonds and SSeS angle deformations.The observed frequencies are reproduced to within 0.5percent for all three molecules.