On the structures and bonding in boron-gold alloy clusters: B6Aun− and B6Aun (n = 1−3)

Abstract

Photoelectron spectroscopy and density-functional theory are combined to investigate the electronic and structural properties of a series of B-Au alloy clusters: B6Aun(-) and B6Aun (n = 1-3). Rich spectral features are observed for each species, and vibrational structures are resolved for numerous detachment transitions of B6Au(-) and B6Au2(-). Electron affinities of B6Aun (n = 1-3) are evaluated to be 2.70 ± 0.03, 2.91 ± 0.02, and 3.21 ± 0.05 eV, respectively. Global structural searches are performed for both the anions and their neutrals. The calculated electronic binding energies are compared with experimental measurements to establish the anion global-minimum structures and their corresponding neutral states. The ground-state structures of these clusters are shown to be planar or quasi-planar with an elongated B6 core, to which the first and second Au atoms are bonded terminally and the third Au in a bridging position. All three anion clusters are π antiaromatic. Natural bond orbital analyses show that the B-Au bonding is highly covalent, providing new examples for the Au∕H analogy in Au alloy clusters.

Four Decades of the Chemistry of Planar Hypercoordinate Compounds

“…[111] A typical case is B 13 + , [112] which has anomalously high stability and low reactivity in comparison with other cationic boron clusters,c onsistent with its aromatic nature.R ecently,A lexandrova and co-workers predicted B 13 + to be ap hotodriven molecular Wankel engine,w hich can be driven by circularly polarized infrared electromagnetic radiation. [113] Additionally,Wang and co-workers prepared and characterized several boron-gold alloy clusters (Figure 45), such as B 6 Au n À (n = 1-3) [114] and B 7 Au 2 À , [115] which contain planar tetracoordinate boron motifs.…”

“…[28] Encouraged by the fact that the planar boron rings can serve as convenient frameworks for the stabilization of planar tetra-and hypercoordinate main-group elements,M inyaev and co-workers [121] predicted the species 47 a-e,w ith planar tetracoordinate nitrogen atoms (Figure 47). 1-3), [114] and B 7 Au 2 À . [115] The bond lengths are given in .…”

Gas phase anion photoelectron spectroscopy and theoretical investigation of gold acetylide species

“…In organometallic chemistry, the isolable analogy between a gold phosphine unit (AuPR 3 ) and a hydrogen atom has been well recognized in the 1980s, 58,59 and recently Au/H analogy has been found in a number of gas-phase complexes, such as Au− −Si, [60][61][62] Au− −B alloy clusters, [63][64][65][66][67] which has been held to originate from the similar electronegativity between Si/B and Au,moreover, the single hydrogen atom in the environment of an Au cluster behaves like the Au atom reported by Ganteför and co-workers. 68 In our experimental spectra of AuC 2 H and AuC 2 Au , both of spectral features including VDEs and HOMO-LUMO gaps resemble, implying their electronic structures to be similar.…”

Vier Jahrzehnte Chemie der planar hyperkoordinierten Verbindungen

“…Wang und Mitarbeiter stellten weitere verschiedene Bor‐Gold‐Legierungscluster dar und charakterisierten diese (Abbildung 45), wie B 6 Au n − ( n =1–3)114 und B 7 Au 2 − ,115 die planar tetrakoordinierte Bormotive enthalten.…”

“… Experimentelle und theoretische globale Minimumstrukturen von B 6 Au n − ( n =1–3)114 und B 7 Au 2 − 115. Die Bindungslängen sind in Å gegeben.…”