Gas Phase Preparation of the Elusive Monobridged Ge(μ‐H)GeH Molecule through Nonadiabatic Reaction Dynamics

Abstract

The hitherto elusive monobridged Ge(μ‐H)GeH (X1A′) molecule was prepared in the gas phase by bimolecular reaction of atomic germanium with germane (GeH4). Electronic structure calculations revealed that this reaction commenced on the triplet surface with the formation of a van der Waals complex, followed by insertion of germanium into a germanium‐hydrogen bond over a submerged barrier to form the triplet digermanylidene intermediate (HGeGeH3); the latter underwent intersystem crossing from the triplet to the singlet surface. On the singlet surface, HGeGeH3 predominantly isomerized through two successive hydrogen shifts prior to unimolecular decomposition to Ge(μ‐H)GeH isomer, which is in equilibrium with the vinylidene‐type (H2GeGe) and dibridged (Ge(μ‐H2)Ge) isomers. This reaction leads to the formation of cyclic dinuclear germanium molecules, which do not exist on the isovalent C2H2 surface, thus deepening our understanding of the role of nonadiabatic reaction dynamics in preparing nonclassical, hydrogen‐bridged isomers carrying main group XIV elements.

Gas-Phase Preparation of 1-Germavinylidene (H2CGe; X1A1), the Isovalent Counterpart of Vinylidene (H2CC; X1A1), via Non-adiabatic Dynamics through the Elementary Reaction of Ground State Atomic Carbon (C; 3P) with Germane (GeH4; X1A1)

“…Experimental Section . The C–GeH 4 reaction was performed at the University of Hawaii . The helium-seeded supersonic beam of ground state atomic carbon was prepared via ablation of a graphite rod .…”

“…The C−GeH 4 reaction was performed at the University of Hawaii. 37 The helium-seeded supersonic beam of ground state atomic carbon was prepared via ablation of a graphite rod. 38 The pulsed carbon beam was characterized by a peak velocity v p of 2560 ± 52 m s −1 .…”

A wealth of structures for the Ge2H2+ radical cation: comparison of theory and experiment

“…Harmonic CCSD/cc-pVTZ ZPVE corrected CCSD(T)/CBS//CCSD/cc-pVTZ relative energies for the neutral Ge 2 H 2 species were computed by Kaiser and coworkers, which were butterfly, monobridged (8.4 kcal mol −1 ), germylidene (10.5), and trans (15.8). 18 Ge + GeH 4 → Ge 2 H 2 + H 2 …”

Low-Temperature Gas-Phase Formation of Methanimine (CH2NH; X1A′)─the Simplest Imine─under Single-Collision Conditions

“…This is achieved by transforming the data from the laboratory frame to the CM frame. 36,37 This yields the CM translational energy, P(E T ), and angular T(θ) flux distributions (Figure 2). Best fits of the experimental data are achieved with a single channel involving the D1methylidyne (CD) versus atomic hydrogen (H) exchange pathway with a product mass combination of 30 amu (H 2 DCN) plus 1 amu (H; reaction 1).…”

“…Under single collision conditions, the primary reaction products "fly away" unperturbed without consecutive reactions like dimerization. 36 The advantages of the crossed molecular beam experiments in studying the reaction mechanisms are demonstrated in the formation of a molecule (D1-methanimine) with a highly reactive carbon−nitrogen double bond. The reaction dynamics of the CH−NH 3 system are quite distinct from those of the isovalent SiH−NH 3 system.…”