Frequency-dependence of the polarizability anisotropy of CO2 revisited

We present extended determinations of the polarizability anisotropy kappa(omega) of CO2 at 514.5 and 488.0 nm by means of measuring the depolarization ratio rho(omega) of linearly polarized laser light. Taking into account the hitherto reported data on rho(omega) as well as experimental data on the mean polarizability alpha(omega) and additional information derived from Kerr-effect measurements, we obtain a value of the static polarizability anisotropy of CO2 of kappa(0) = 15.2(1.6) au. The large uncertainty of approximate to 10% results from the fact that all available experimental information is used to obtain an estimate of the static polarizability ansiotropy of CO2. This zero-frequency value, which includes the vibrational part of the static anisotropy, is in reasonable agreement with hitherto reported experimental data and in good accordance with new ab initio calculations. (C) 2000 Elsevier Science B.V. All rights reserved.