XPS EVIDENCE FOR THE PHOTOPRODUCTION OF TUNGSTEN(VI) CYANO COMPLEXES IN CHARGE-TRANSFER PHOTOCHEMISTRY OF W(CN)8(3-) ION IN NONAQUEOUS SOLVENTS

The X-ray photoelectron spectra of a series of cyano complexes of tungsten were measured in order to obtain the W4f and N1s binding energies. A correlation between the W4f binding energies and oxidation state of tungsten and N1s core binding energies as a function of chemical environment allowed the identification of three new photoproducts isolated from irradiated octacyanotungstate(V) ion in MeCN. The new species have been found to consist of W(VI) centres and assigned to seven-coordinate mononuclear W(VI)(CN)7-, dinuclear (CN)6-W(VI)-NC-W(VI)(CN)6- and trinuclear (CN7-W(VI)-NC-W(IV)(CN)6-CN-W(VI)(CN)7(6-) complex anions.