STATIC AND DYNAMIC POLARIZABILITIES, CAUCHY COEFFICIENTS AND THEIR ANISOTROPIES - A COMPARISON OF STANDARD METHODS

The static and dynamic polarisabilities of a range of small molecules have been calculated and compared with earlier experimental and comput ational work. The polarisabilities have been calculated using SCF and density functional theory (DFT) methods, the latter using local and no n-local, hybrid functionals. Calculations at several low frequencies e nable the Cauchy moment S(-4) to be found for both the isotropic and a nisotropic polarisabilities. Results have been computed using two basi s sets, Sadlej's medium-size polarized basis set and Dunning's correla tion consistent triple-zeta basis set augmented with additional polari sation functions. The DFT values obtained with the hybrid functional a re in good agreement with both experimental values and coupled-cluster results. (C) 1998 Elsevier Science B.V. All rights reserved.