Theoretical study of the electronic spectrum of binuclear gold(I) complexes

The electronic structure and the spectroscopic properties of [Au-2(CS3)(2)](-2), [Au-2(pym-2-S)(2)] (pym = pyrimidethiolate), [Au-2(dpm)(2)](+2) (dpm = bis(diphosphino)methane) were studied using density functional theory (DFT) at the B3LYP level. The absorption spectrum of these binuclear gold(l) complexes was calculated by single excitation time-dependent (TD) method. All complexes showed a (1)(5d sigma* -> 6p sigma) transition associated with a metal-metal charge transfer, which is strongly interrelated with the gold-gold distance. Furthermore, we have calculated the frequency of the gold-gold vibration (nu(Au2)) on the above complexes. The values obtained are theoretically in agreement with experimental range