Crystal field splitting in the far infrared spectrum of rhombic sulfur

Abstract

The infrared (i.r.) spectra of thin polycrystalline samples of orthorhombic sulfur at 95 °K in the range 50–500 cm−1 have been recorded. The three i.r. active fundamentals ν4, ν5, and ν6 are observed to be split into 2,3, and 3 components, respectively, as predicted from a group theoretical analysis of the unit cell symmetry, thus confirming the assignment of ν4 and ν6. Several weaker absorptions are assigned by comparison with recent Raman results and a normal coordinate analysis. No peaks assignable to lattice vibrations are observed.