Reactions of Ti, Zr, and Hf Atoms with Hydrogen Sulfide: Argon Matrix Infrared Spectra and Theoretical Calculations

Abstract

Laser-ablated Ti, Zr, and Hf atoms have been codeposited at 4 K with hydrogen sulfide in excess argon. The metal atoms insert into the S-H bond of hydrogen sulfide to form the HMSH, H2MS, and H2M(SH)2 molecules (M = Ti, Zr, Hf), which were identified on the basis of the D2S and H2(34)S isotopic substitutions. The observed vibrational frequencies of these species were reproduced by B3LYP functional calculations. The reaction mechanisms have been proposed on the potential energy surface of the studied system to account for the formation of these molecules. We have made a theoretical prediction about the H2MS complexes dehydrogenation, which can provide a novel proposal for generating hydrogen from H2S.

Splitting of Hydrogen Sulfide by Group 14 Elements (Si, Ge, Sn, Pb) in Excess Argon at Cryogenic Temperatures

“…■ EXPERIMENTAL AND COMPUTATIONAL METHODS Laser-ablated group 14 atoms (Si, Ge, Sn, Pb) were reacted with H 2 S in excess argon during condensation at 4 K using a Sumitomo Heavy Industries RDK-205D cryocooler, and the methods were described previously. 15,16 New species that formed in solid matrix were identified and characterized from matrix isolation infrared spectra using H 2 S, H 2 34 S and D 2 S reagents. The Nd:YAG laser fundamental (Continuum Minilite II, 1064 nm, 15 Hz repetition rate with 5 ns pulse width) was focused (about 10 mJ/pulse) onto silicon, germanium, tin and lead targets (Alfa Aesar), which produced bright plumes from the target surfaces spreading uniformly to the 4 K CsI window.…”

Silicon Tetrahydroborate and Silylene Dihydroborate with Interelement B–H–Si and B═Si Bonds

“…■ EXPERIMENTAL AND COMPUTATIONAL METHODS Our experimental method has been described in detail previously. 37,38 Laser-ablated natural isotopic boron n B (Aldrich, 80.4% 11 B, 19.6% 10 B), enriched 10 B (Eagle Pitcher, 93.8% 10 B, 6.2% 11 B), or enriched 11 B (Eagle Pitcher, 97.5% 11 B, 2.5% 10 B) was co-deposited with silane in excess argon onto a 4 K CsI window, which was mounted onto cold tip closed-cycle helium refrigerator (Sumitomo Heavy Industrious, Model RDK408D) for 1 h at a rate of 2−4 mmol/h. Typically, 10−30 mJ/pulse laser power was used.…”

Double and Triple Si–H–M Bridge Bonds: Matrix Infrared Spectra and Theoretical Calculations for Reaction Products of Silane with Ti, Zr, and Hf Atoms

“…In experiments for the Hf reactions with SiH 4 in argon (Figure ), two bands at 1675.5, and 1654.0 cm –1 in the Hf–H stretching region show similar behaviors on deposition, annealing, and irradiations. These frequencies are near the Hf–H stretching frequencies at 1666.8 and 1640.2 cm –1 for SHfH 2 molecule in solid argon but higher than the same modes at 1614.2 and 1563.6 cm –1 for the CH 2 HfH 2 molecule and at 1637.8 and 1629.1 cm –1 for the isolated HfH 2 molecule in solid argon . A new molecule with the HfH 2 subunit comes into mind.…”

“…First, the observed bands at 1597.6 and 1577.9 cm –1 are appropriate for Zr–H stretching modes of a ZrH 2 subunit. Recall for the isolated ZrH 2 molecule in solid argon the weaker and stronger Zr–H symmetric and antisymmetric stretching modes are at 1557.8 and 1524.8 cm –1 , and two similar modes for the ZrH 2 subunit in the SZrH 2 molecules are at 1598.8 and 1569.7 cm –1 . The methane product CH 2 ZrH 2 in argon exhibits bands at 1581.0 and 1546.2 cm –1 for two Zr–H stretching modes .…”