Relativistic effects in gold chemistry. I. Diatomic gold compounds

Abstract

Molecular density functional calculations in the regular relativistic approximation: Method, application to coinage metal diatomics, hydrides, fluorides and chlorides, and comparison with first-order relativistic calculations Nonrelativistic and relativistic Hartree-Fock (HF) and configuration interaction (CI) calculations have been performed in order to analyze the relativistic and correlation effects in various diatomic gold compounds, It is found that relativistic effects reverse the trend in most molecular properties down the group (11). The consequences for gold chemistry are described. Relativistic bond stabilizations or destabilizations are dependent on the electronegativity of the ligand, showing the largest bond destabilization for AuF (86 kJlmol at the CI level) and the largest stabilization for AuLi ( -174 kJ Imol). Relativistic bond contractions lie between 1.09 (AuH+) and 0.16 A (AuF). Relativistic effects of various other properties are discussed. A number of as yet unmeasured spectroscopic properties, such as bondlengths ('e), dissociation energies (De)' force constants (k e ), and dipole moments (f1e), are predicted.

Experimental and theoretical studies of diatomic gold halides

“…For bromine and iodine, the Stuttgart pseudopotential combinations were altered to give (211111/21111/11/1) and (2111111/1111111/11/1) sets for Br and I, respectively, with basis sets, pseudopotentials, and extra d-and f functions taken from refs. [16], [27], and [28]. In the course of these studies, also some calculations at the MP 2 level were performed including Mulliken population analysis.…”

“…As far as experimental determinations of the bond dissociation energies (BDEs) of AuX diatomics are concerned, only some extrapolations from spectroscopy [6,8] and a few ion/ molecule bracketing data are available [9,10]. In marked contrast, numerous theoretical studies appeared on these species [11][12][13][14][15][16][17]. However, also the theoretical predictions show a considerable spread (Table 1).…”

The chemistry of gold-fluoro compounds: A continuing challenge for gold chemists

“…The crystal structure of O2[AuF6] (11) has been determined and the Au-F bond lengths were measured to be 1.875(9), 1.895(9) and 1.889(10) Å for the equatorial and axial fluorides, respectively (49,61,62). The X-ray crystal structure of [KrF][AuF6] (12) has also been determined (62).…”

“…More recently, Schwerdtfeger and his group have studied in some detail the properties of AuF and related species using high-level computational methods and have predicted its existence in the gas phase (9)(10)(11)(12)(13)(14)(15). In 1994 Schwarz and co-workers unambiguously identified AuF in the gas phase using neutralization-reionization mass spectrometry (16 …”

Homogeneous Gold Catalysis: Mechanism and Relativistic Effects of the Addition of Water to Propyne

“…For Au we used a scalar relativistic energy-consistent small-core pseudopotential of the Stuttgart group. To estimate the influence of relativistic effects, a non-relativistic pseudopotential [32] with the accompanying basis set by Schwerdtfeger and Wesendrup was used [33]. Solvent effects were taken into account by calculating selfconsistent polarizable continuum model (PCM) single points at the previously obtained structures with methanol as a solvent [34,35].…”