Mass spectrometric study of transition metal Oxo- and thiohalides

DONALD L. SIKGLETON AND FRED E. STAFFORD

1208 Inorganic Chemistry, Vol. 11, No. 6, 1972 CONTRIBUTION FROM

THE

DEPARTMENT OF CHEMISTRY A N D THE MATERIALS RESEARCH CENTER, NORTHWESTERN UNIVERSITY, EVANSTON, ILLINOIS 60201

A Mass Spectrometric Study of Transition Metal Oxo- and Thiohalidesl BY DONALD L. SIKGLETON

AND

F R E D E. STAFFORD*

Receiued October 7, 1971 A molecular beam mass spectrometric study of MoOC14, WOCI?, WSC14, ReOC14, and OsOCla shows the vapors to be comprised primarily of the corresponding monomers. Because of the synthesis used, the vapor above a sample of \\‘OBra gave rise t o the ions W2Br,+ (3 5 12 5 6 ) (from W2Br6) and contained the molecules WBr6 or WBr6. All the oxo- and thiotetrahalides reacted with surfaces of the mass spectrometer to give volatile products and are likely to do so in microwave, electron diffraction, or matrix-isolation apparatuses. Other new species observed as impurities and/or reaction products are MoOzBrCI, W2Br,Cl,’ (x. y 5 6, from the corresponding neutrals), WOSCL, WS2C12, Re02C12+,OsO,Cl+(?), OsO2C12+, and Os02Clf. (The neutral progenitors of the species listed only as ions were not identified.) The fragmentation patterns of MoOCla, WOC14, WOBr4, and WSCL are similar with very weak (