Collision-induced depolarized scattering by CF4 in a Raman vibrational band

Collision-induced scattering data have been recorded at room temperature for gaseous tetrafluoromethane in a frequency vicinity of the Raman vibrational line ν1=908 cm−1. For the first time, corresponding binary depolarized intensities have been measured in absolute units for frequency shifts up to 110 cm−1 from the band center. Comparison with theoretical semiclassical intensities computed from dipole-induced dipole and dipole-multipole light scattering mechanisms leads to an evaluation of the first derivative of the dipole-quadrupole polarizability tensor A′. This result is in good agreement with recent ab initio quantum-chemistry calculations of the CF4 multipolar polarizabilities.