Orientational ordering and site structure for CCl4 in a krypton matrix

Infrared studies of the ν3 and ν1+ν4 modes of CCl4 trapped in krypton matrices show that the CCl4 molecules adopt two sites, one of which preserves the triple degeneracy while the other shows site symmetry splitting and a high degree of orientational ordering. At deposition temperatures above 35 K the orientational ordering of the low symmetry site is diminished as is the relative concentration of this site compared to the other. The results suggest that both cubic-close-packed and hexagonal-close-packed environments exist in these matrices. Significant differences in the ν3 vs ν1+ν4 line widths have been observed and attributed to rapid V–V energy transfer from the higher to the lower of these Fermi coupled modes.