Directed Gas Phase Formation of Silene (H₂SiCH₂)

Abstract

The silene molecule (H2SiCH2; X1A1) has been synthesized under single collision conditions via the bimolecular gas phase reaction of ground state methylidyne radicals (CH) with silane (SiH4). Exploiting crossed molecular beams experiments augmented by high‐level electronic structure calculations, the elementary reaction commenced on the doublet surface through a barrierless insertion of the methylidyne radical into a silicon‐hydrogen bond forming the silylmethyl (CH2SiH3; X2A′) complex followed by hydrogen migration to the methylsilyl radical (SiH2CH3; X2A′). Both silylmethyl and methylsilyl intermediates undergo unimolecular hydrogen loss to silene (H2SiCH2; X1A1). The exploration of the elementary reaction of methylidyne with silane delivers a unique view at the widely uncharted reaction dynamics and isomerization processes of the carbon–silicon system in the gas phase, which are noticeably different from those of the isovalent carbon system thus contributing to our knowledge on carbon silicon bond couplings at the molecular level.

Directed Gas Phase Formation of the Elusive Silylgermylidyne Radical (H3SiGe, X2A′′)

“…Although considerable research has been conducted in understanding the chemical bonding and structures of the homonuclear (C 2 H 3 , Si 2 H 3 , Ge 2 H 3 ) [3b,c,11,12c] and heteronuclear systems (SiCH 3 , GeCH 3 ), [14a,b,16] special attention was attributed to the experimental characterization of hydrogenated silicon‐germanium species (GeSiH x ). Due to the their technological applications such as chemical vapor deposition, [17] semiconductor processing, [18] silicon‐germanium nanowires, [19] germanium‐silicon films, [20] and modulation doped field effect transistors (MODFET), [21] the structures, energetics, and spectroscopic properties of silicon‐germanium clusters have attracted considerable interest.…”