POLARIZABILITIES, ATOMS-IN-MOLECULES POLARIZABILITIES AND BONDING IN (CN)(-), (SCN)(-), (OCN)(-) AND (CLO)(-)

The gas-phase structures and dipole polarizabilities of cyanide, cyanate, thiocyanate and hypochlorite anions have been computed at various levels of theory up to MP4 (SDTQ). Electron correlation typically accounts for some 17 of the total polarizability. Second-order Moller-Plesset corrections appear to dominate the correlation contribution to the polarizability. An atoms-in-molecules decomposition of the polarizability tensors provides insight into the atomic origin of the polarizability contributions, shows some transferability for the cyano nitrogen atoms, and may find application in the construction of anisotropic intermolecular dispersion potentials. The bonding in these anions is discussed also in the framework of a bond critical point analysis of the electron density rho, the del(2) rho distribution, and bond dissociation energies.