Fragmentation of Alkyldisilane Ions in EIMS I. 1,1,2,2-Tetramethyldisilane.

Abstract

The fragmentation of 1,1,2,2-tetramethyldisilane by using a deuterium labeling technique, a B/E linked scanning technique and ab initio MO methods was studied. In 70eV-EIMS the base peak was observed at m/z 59, which is produced by the simple cleavage of an Si-Si bond. It was confirmed by the ab initio MO calculation that the formation of this ion might occur predominantly. It was concluded that the abundant ion at m/z 73 was produced by a 1,2-hydrogen shift from one silicon atom to the other with simultaneous reverse shift of a methyl group.