What determines the solvatochromism of metal-to-ligand charge transfer transitions? A demonstration involving 17 tungsten carbonyl complexes

摘要: Abstract A consistent model which permits rationalization and estimation of the solvatochromic behaviour coordination compounds with metal-to-ligand charge transfer absorption bands is described. The shows how changing relationship between metal-ligand bond polarities in ground MLCT excited state determines whether negative, positive, or no solvatochromism results. Data for seventeen mononuclear binuclear tetra- pentacarbonyltungsten complexes are analyzed order to illustrate substantiate different electronic situations leading various degrees solvatochromism. Ligand basicities, calculated Huckel molecular orbital coefficients, ESR coupling constants, metal fragment oxidation potentials used estimate ability fragments ligands resulting complexes.