PNNL

Abstract

Unlike the very labile, unobservable radical cations {[CpM(CO)3]2}+• (M = W, Mo), derivatives {[CpM(CO)2(PMe3)]2}+• are stable enough to be isolated and characterized. Experimental and theoretical studies show that the shortened M-M bonds are of order 1½ (1s + ½p), and that they are not supported by bridging ligands. The unpaired electron is fully delocalized, with a spin density of ca. 45% on each metal atom. We thank the U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Biosciences and Geosciences for support of this work. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for DOE by Battelle. The EPR and computational studies were performed using EMSL, a national scientific user facility sponsored by the DOE’s Office of Biological and Environmental Research and located at PNNL. We thank Dr. Charles Windisch for access to his UV-Vis-NIR spectrometer.