Production of binary oxides by photolysis of M(CO)6 molecules (M = Cr, Mo, or W) isolated in O2-doped argon matrices

Abstract

Oxides of the metals chromium, molybdenum, and tungsten have been generated by u.v. photolysis of O₂-doped argon matrices containing [M(CO)₆] molecules (M = Cr, Mo, or W) at ca. 20 K. In addition to CO and CO₂, produced irrespective of the nature of M, the final products of photolysis are MO₂(M = Cr) and MO₃(M = Mo and W). The MO₃ molecules are produced from another metal oxide species, (X), and studies involving ¹⁸O substitution for the tungsten version suggest that (X) is a peroxide (η²-O₂)WO₂. U.v. photolysis of (X) yields MO₃ and O atoms in the excited ¹D state. The presence of the O(¹D) atoms is demonstrated by experiments in which O₃ is produced in pure dioxygen matrices, N₂O in O₂-doped dinitrogen matrices, and CH₃OH and H₂CO in O₂-doped methane matrices.