The previously unknown silylgermylidyne radical (H3SiGe; X2A′′) was prepared via the bimolecular gas phase reaction of ground state silylidyne radicals (SiH; X2Π) with germane (GeH4; X1A1) under single collision conditions in crossed molecular beams experiments. This reaction begins with the formation of a van der Waals complex followed by insertion of silylidyne into a germanium‐hydrogen bond forming the germylsilyl radical (H3GeSiH2). A hydrogen migration isomerizes this intermediate to the silylgermyl radical (H2GeSiH3), which undergoes a hydrogen shift to an exotic, hydrogen‐bridged germylidynesilane intermediate (H3Si(μ‐H)GeH); this species emits molecular hydrogen forming the silylgermylidyne radical (H3SiGe). Our study offers a remarkable glance at the complex reaction dynamics and inherent isomerization processes of the silicon‐germanium system, which are quite distinct from those of the isovalent hydrocarbon system (ethyl radical; C2H5) eventually affording detailed insights into an exotic chemistry and intriguing chemical bonding of silicon‐germanium species at the microscopic level exploiting crossed molecular beams.
The chemical dynamics of the elementary reaction of ground state atomic silicon (Si;3P) with germane (GeH4; X1A1) were unraveled in the gas phase under single collision condition at a collision energy of 11.8±0.3 kJ mol−1exploiting the crossed molecular beams technique contemplated with electronic structure calculations. The reaction follows indirect scattering dynamics and is initiated through an initial barrierless insertion of the silicon atom into one of the four chemically equivalent germanium‐hydrogen bonds forming a triplet collision complex (HSiGeH3;
- Award ID(s):
- 1853541
- NSF-PAR ID:
- 10248966
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemPhysChem
- Volume:
- 22
- Issue:
- 14
- ISSN:
- 1439-4235
- Page Range / eLocation ID:
- p. 1497-1504
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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