M–S Multiple Bond in HMSH, H₂MS, and HMS Molecules (M = B, Al, Ga): Matrix Infrared Spectra and Theoretical Calculations

Abstract

Reaction products of B, Al, and Ga atoms with H2S have been identified in solid argon using matrix isolation infrared absorption spectroscopy. The results show that the ground state B atom reaction with H2S gives the H2BS molecule while for the Al atom the HAlSH molecule forms first, which then further isomerizes to H2AlS upon >500 nm irradiation. The reaction of the Ga atom with H2S only takes place upon photolysis to produce HGaSH in the matrix. The assignments of the major modes for these products were confirmed by appropriate 10B, 11B, D2S, and H2 34S isotopic shifts and theoretical frequency calculations. Topological analysis of the electron density suggests that both HBSH and H2BS molecules possess covalent B–S bond with significant double bond character, while the M–S bond in the heavier group 13 homologues (Al, Ga) was characterized as a polar covalent strong interaction.

M←NCCH3, M-η2-(NC)–CH3, and CN–M–CH3 Prepared by Reactions of Ce, Sm, Eu, and Lu Atoms with Acetonitrile: Matrix Infrared Spectra and Theoretical Calculations

“…Matrix/reagent samples were codeposited onto a cryogenic CsI window maintained at 4 K (Sumitomo Heavy Industries Model RDK 205D). The detailed experimental description is reported in previous publications. − After initial reaction, infrared spectra were recorded on a Bruker 80V spectrometer at a resolution of 0.5 cm –1 between 4000 and 400 cm –1 using a HgCdTe range B (4000–440 cm –1 ) detector. Then, the matrix samples were annealed and irradiated by a mercury arc lamp (Philips, 175 W) for 6 min periods to record more spectra.…”

Highly accurate CCSD(T) homolytic Al–H bond dissociation enthalpies – chemical insights and performance of density functional theory

“…[12,13] A number of substituted aluminium-centred radicals have also been produced including: CH 3 AlH, [14] HAlNH 2 , [15][16][17] Al(NH 2 ) 2 , 17 HAlPH 2 , [18,19] HAlOH, [20] Al (OH) 2 12 and HAlSH. [21] The present study addresses the gap in the literature concerning the extent to which substituents affect the strength of Al-H bonds toward homolytic dissociation. To achieve this, we report a high-level quantum chemical investigation (performed using the W2w thermochemical protocol), in which the gas-phase homolytic BDEs of a set of 18 aluminium hydrides (i.e.…”

Activation of H2S by Atomic Cr, Mn, and Fe: Matrix Infrared Spectra and Quantum Chemical Calculations

“…The experimental results indicate that the reaction between Cr and H 2 S only takes place after the excitation of chromium atoms to the Cr:z 7 P­(3d 5 4p 1 ) excited state on >400 nm photolysis. Theoretical studies indicate that the first step for the inserting reaction is the formation of the MSH 2 complex by the approaching of transition metal atoms to H 2 S molecules. , As shown in Figure , the interaction energy between ground-state Cr and H 2 S is 1.36 kcal/mol at a Cr–S distance of 3.1 Å, which is assigned to the van der Waals force. A stable complex could be formed between excited-state Cr:z 7 P­(3d 5 4p 1 ) atoms and H 2 S with a binding energy of 31.6 kcal/mol at a Cr–S bond length of 2.35 Å (Figure ).…”