SPLITTING OF THE 1S(-1)3P RESONANCE AT THE SULFUR ATOM IN PLANAR SULFUR GOLD COMPLEXES

Results of experimental and theoretical investigation of X-ray absorpt ion S K near edge structure in gold complex compounds with isomaleonit rildithiolate and isomaleonitrilthioselenolate ligands are presented. In the framework of a quasi-atomic model the splitting of the 1s(-1)3p resonance at the sulfur atom has been found to dominate the S K XANES . Approximating the surrounding effect by fragments which include all sulfur and gold atoms a threefold splitting of the resonance was obtai ned. The components may be attributed to particular sigma and pi antib onding electronic states of the complex molecule. Comparing the result s for both complexes the strong influence of the local structure on th e resonance splitting is elucidated.