Abstract
The transition energies and intensity distributions in the ligand-field spectra of K2PtCl4 and K2PtBr4 are quantitatively reproduced within the cellular ligand-field approach. The energy and intensity parameters provide a realistic and consistent account of the electron distribution in these third row transition-metal chromophores. The intensity arises dynamically through the molecular vibration modes. The parameters for the three ungerade bending modes in the molecular D 4h symmetry are of similar magnitude, a result that is consistent with the nearly equal frequencies of these vibrations. Analyses of the transition energies of the analogous palladium(II) complexes are consistent with the studies of the platinum(II) species.