The covalent interaction between dihydrogen and gold: A rotational spectroscopic study of H2–AuCl

Abstract

The pure rotational transitions of H-AuCl have been measured using a pulsed-jet cavity Fourier transform microwave spectrometer equipped with a laser ablation source. The structure was found to be T-shaped, with the H-H bond interacting with the gold atom. Both Cl andCl isotopologues have been measured for both ortho and para states of H. Rotational constants, quartic centrifugal distortion constants, and nuclear quadrupole coupling constants for gold and chlorine have been determined. The use of the nuclear spin-nuclear spin interaction terms D, D, and D for H were required to fit the ortho state of hydrogen, as well as a nuclear-spin rotation constant C. The values of the nuclear quadrupole coupling constant of gold are χ=-817.9929(35) MHz, χ=504.0(27) MHz, and χ=314.0(27). This is large compared to the eQq of AuCl, 9.63 312(13) MHz, which indicates a strong, covalent interaction between gold and dihydrogen.

Benchmarking the quadrupolar coupling tensor for chlorine to probe weak-bonding interactions

“…In addition to rotational constants, quantum chemical methods produce predictions for another characteristic important for assignment, the Nuclear Quadrupolar Coupling Constant (NQCC) w ij . Provided the target molecule contains one or more quadrupolar nuclei (I 4 1/2), such as 14 N or 35 Cl, [6][7][8][9] a hyperfine structure is observed that arises from the coupling of the nuclear angular momentum with the molecular angular momentum. 10 The coupling is dependent on the intrinsic nuclear quadrupole moment Q and the electronic environment expressed by the Electronic Field Gradient (EFG) q ij (i, j = abc).…”

Understanding Regium Bonds and their Competition with Hydrogen Bonds in Au2:HX Complexes

“…The structure of the OC : AuX (with X=F, Cl and Br), H 2 S : AuI, and H 2 : AuCl complexes has been determined by microwave spectroscopy and theoretical calculations in which the AuX molecules act as electron acceptors and the electron donor lies along the symmetry axes of the AuX molecule. The possibility of Au nanoparticles (AuNP) acting as electron donor has also been explored, particularly the interaction of iodoperfluorobenzene compounds with gold nanoparticles has been investigated by different spectroscopic techniques and it was found that gold nanoparticles can form stable complexes with small molecules through halogen bonds.…”

Molecular geometries and other properties of H2O⋯AgI and H3N⋯AgI as characterised by rotational spectroscopy and ab initio calculations

“…Microwave spectroscopy has recently been applied to explore the molecular structures of complexes in which a Lewis base is attached to either CuX, AgX, or AuX (where X is a halogen atom) to form L· · · MX, [1][2][3][4][5][6][7][8][9][10][11] where, for example, L = H 2 O, 1,10 H 2 S, 3-5 NH 3 , 12 C 2 H 2 , 6,8,11 or CO. 13,14 The same technique has also been applied to study complexes that are similar in composition and structure but distinct in that L is not a typical Lewis base. For example, H 2 · · · MX, 15,16 Ar· · · MX, [17][18][19] Kr· · · MX, 18,20 and Xe· · · MX 21 have each been characterised. Significant structural changes were identified in each of H 2 , 15,16 C 2 H 2 , 6,8,11 and C 2 H 4 6 on their attachment to a coinage metal atom.…”