Infrared Spectra and DFT Calculations for the Coinage Metal Hydrides MH, (H₂)MH, MH₂, M₂H, M₂H^-, and (H₂)CuHCu in Solid Argon, Neon, and Hydrogen

Abstract

Laser-ablated coinage metal atom reactions with H2 in excess argon, neon, and pure hydrogen are investigated through matrix infrared spectroscopy. The reaction products are identified by isotopic substitution (D2, HD, and H2 + D2) and verified by DFT calculations of vibrational fundamentals. The MH and (H2)MH molecules are observed for all group 11 metals, and the trihydride complex (H2)AuH3 is stabilized in pure hydrogen. The (H2)CuH and (H2)AgH complexes exhibit weak H−H stretching fundamentals at 3805.9 and 3566.6 cm-1 and strong Cu−H and Ag−H stretching modes at 1861.4 and 1742.6 cm-1, respectively. In addition, (H2)CuH reacts further with Cu to give (H2)CuHCu, and Au (2P) inserts to form AuH2 in pure hydrogen. The cluster hydrides M2H and M2H- anions are also formed in these experiments.