Melissa L. Golden

Capture of NiII, CuI and ZnII by thiolate sulfurs of an N2S2Ni complex: A role for a metallothiolate ligand in the acetyl-coenzyme A synthase active site

The metal binding affinity of an (N2S2)Ni bridging metallothiolate ligand (Zn2+ < Ni2+ < Cu+) gives precedent for the observed heterogeneity in ACS/CODH.

The Vapochromic Behavior, Desulfoxidation and Structural Characterization of the SO2 Adducts of Ni(BME‐DACH) from Powder Data

Ab‐initio structure determination of Ni(BME‐DACH) · SO2 has been carried out by a combination of real space methods and Rietveld analysis from powder X‐ray diffraction patterns obtained from microgram quantities of the compound mounted on a nylon loop (space group. P21/c, a = 8.871(1), b = 14.480(1), c = 10.576(1) Å, β = 95.98(1)°. The structure of Ni(BME‐DACH) · SO2 shows that Ni(BME‐DACH) complex remains intact and is related to the structure of Ni(BME‐DACH) · 2SO2, providing a platform for SO2 binding. We have also followed the desulfoxidation of the 2SO2 adduct by in‐situ micro‐powder X‐ray diffraction and, based on the results, a mechanism is proposed. We acknowledge the financial support of the National Science Foundation (Grants CHE 01‐11629 to MYD for this work and CHE 98‐07975 for the purchase of X‐ray equipment) and contributions from the Robert A. Welch Foundation. Use of the Advanced Photon Source was supported by the U. S. Department of Energy, Basic Energy Sciences, Office of Science, under Contract No. W‐31‐109‐Eng‐38.