ELECTRIC-DIPOLE POLARIZABILITIES OF NEGATIVE-IONS OF THE COINAGE METAL ATOMS

The dipole polarizability of the coinage metal anions is calculated in different approximations for both the electron lation and relativisti c effects. The large polarizabilities of these ions give a good illust ration of the performance of different computational methods. The spin -averaged Douglas-Kroll no-pair scheme combined with the CCSD(T) treat ment of the electron correlation predict the following values of polar izabilities: 243 au for Cu-, 213 au for Ag- and only about 93 au for A u-. The non-relativistic CCSD(T) results are 278, 299 and 256 au, resp ectively. Both the non-relativistic and relativistic results agree wit h the QCISD(T) pseudopotential data, though serious discrepancies occu r at the level of the QCISD approximation. The use of the scalar Pauli approximation for the estimation of the relativistic contribution to the dipole polarizabilities of the coinage metal ions is limited to Cu - and Ag-. For Au this approximation strongly overestimates the magnit ude of the relativistic effect.