Studies of Molybdenum-Molybdenum Bonded Species. 1. Synthesis and Characterization of a Reduction Product of Cs sub 3 Mo sub 2 Cl sub 8 H. 2. Mixed Sulfur/Chlorine-Substituted Hexanuclear Molybdenum Clusters

摘要

A black powder isolated from the reaction of Cs sub 3 Mo sub 2 Cl sub 8 H and zinc in refluxing pyridine, Mo sub 1 sub 0 Cl sub 1 sub 1 py sub 0 sub 8 , has been studied. The material is amorphous to x-rays, and the infrared spectrum indicates coordinated pyridine and chlorine. The x-ray photoelectron spectrum indicates one type of molybdenum and shows both terminal and bridging chlorine are present in the ratio of 1.5:1.0. Mo sub 1 sub 0 Cl sub 1 sub 1 py sub 0 sub 8 is stable at elevated temperatures and can be heated in vacuo for over 24 hours at 300 exp 0 C with little change in composition. The best description of this material seems to be a highly bridged, metal-metal bonded cluster or polymer. Mo sub 6 Cl sub 12 has been reacted with various sulfur-containing reagents to prepare mixed chlorine sulfide Mo sub 6 X sub 8 clusters. These clusters have been characterized by x-ray powder diffraction, x-ray photoelectron spectroscopy, and infrared spectroscopy. High reaction temperatures (> 200 exp 0 C) with high ratios of NaSH to Mo sub 6 Cl sub 12 (16:1) result in decomposition of the No sub 6 X sub 8 cluster. Reactions of 1 equivalent of Mo sub 6 Cl sub 12 and 8 equivalents of NaSH at 115 exp 0 C yield amorphous products. Intermediate conditions produce crystalline Mo sub 6 X sub 8 derivatives. These products appear to be solid solutions, or have some amorphous impurity present. A FORTRAN IV computer program for analyzing x-ray photoelectron spectra is described. The program smooths the data, makes baseline and scattering corrections, and fits the corrected spectra with linear combinations of Gaussian and Cauchy functions. The results are useful in inferring structural information. 19 figures, 4 tables. (ERA citation 08:012785)