DFT Insights into the Variety in the Coordination Modes of the Equatorial Halides in [Au₁₃Ag₁₂(PR₃)₁₀X₈]⁺ (X=Cl/Br) Clusters

Abstract

The bonding character within metal nanoclusters represents an intriguing topic, shedding light on the inherent driving force for the packing preference in nanomaterials. Herein, density functional theory (DFT) calculations were conducted to investigate the correlation of the series of isomeric [Au 13 Ag 12 (PR 3 ) 10 X 8 ] + (X=Cl/Br) clusters, which are mainly differentiated by the coordination mode of the equatorial halides (μ 2 -, μ 3 -and μ 4 -) in the rod-like, bi-icosahedral framework. The theoretical simulation corroborates the variety in the configuration of the Au 13 Ag 12 clusters and elucidates the fast isomerization kinetics among the different configurations. The easy tautomerization and the variety in chloride binding modes correspond to a fluxionality character of the equatorial halides and are verified by the potential energy curve analysis. The structural flexibility of the central Au 3 Ag 10 block is the main driving force, while the relatively stronger AgÀ X bonding interaction (compared to that of AuÀ X), and a sufficient number of halides are also requisite for the associating AgÀ X tautomerizations.

Staggered Assembly of a Dimeric Au13 Cluster: Impacts on Coupling of Geometric Isomerism

“…Li et al. observed Au 13 Ag 12 conformational isomerism controlled by temperature, [30] and subsequent studies showed that the driving force for generating this isomerism arises from changes in the coordination mode of the bridging Cl − ligands [52] . Wang et al.…”

“…The coordination mode of the bridging chalcogen or halogen can induce differences in the geometric structures of the obtained bi‐icosahedral assemblies [52] . Li et al.…”

“…The coordination mode of the bridging chalcogen or halogen can induce differences in the geometric structures of the obtained bi-icosahedral assemblies. [52] Li et al observed Au 13 Ag 12 conformational isomerism controlled by temperature, [30] and subsequent studies showed that the driving force for generating this isomerism arises from changes in the coordination mode of the bridging Cl À ligands. [52] Wang et al reported that a larger span of the bridging ligands favors the formation of a staggered arrangement.…”

“…[52] Li et al observed Au 13 Ag 12 conformational isomerism controlled by temperature, [30] and subsequent studies showed that the driving force for generating this isomerism arises from changes in the coordination mode of the bridging Cl À ligands. [52] Wang et al reported that a larger span of the bridging ligands favors the formation of a staggered arrangement. [14] Figure 3e shows the coordination mode of DETC ligands with Au atoms.…”