Exploring the electronic properties and cation complexation of polyoxoaurates [Au^III₄X₄O_m]ⁿ⁻(X = Si^IV, P^V, Ge^IV, As^V, and Se^IV) using quantum chemical calculations

Abstract

Quantum chemical calculations were performed to explore the structural and electronic properties of the two polyoxoaurates, [Au(III)4As(V)4O20](8-) (Au4As4) and [Au(III)4Se(IV)4O16](4-) (Au4Se4), known to date, and a number of hypothetical polyoxoaurate derivatives comprising heteroatoms different from arsenic and selenium (namely, Si, Ge and P). In addition, the interactions of [Au(III)4X4Om](n-) (X = As, Se) with alkali-metal cations (Li(+), Na(+), K(+) and Rb(+)) are also analysed. The studies suggest that the geometry structure, electronic properties and nucleophilicity of oxygen atoms of these polyoxoaurates are tuned by the size or electronegativity of the heteroatoms (Si, Ge, P, As and Se). Then, the geometry of [Au(III)4X4Om](n-) (X = As and Se) coordinating with alkali cations from Li(+) to Rb(+) and the complexation energy between [Au(III)4X4Om](n-) and alkali cations were compared. The results show that the stability and electronic structure of heteropolyoxoaurates depend on the entrapped cations. On the basis of the complexation energy, it can be concluded that the ion-pairing effect in arsenate-capped oxoaurate is stronger than that in selenite-capped oxoaurate. These heteropolyoxoaurates are expected to play a role in aqueous behaviour, self-assembly characteristics of polyoxoaurates, ion recognition, selectivity studies and may exhibit potential guest-switchable redox properties.

Polyoxometalates: Tailoring metal oxides in molecular dimension toward energy applications

“…43,349,[353][354][355][356][357][358][359] A number of other transition metalbased polyoxometalates have been investigated, such as silver-containing polyoxometalates, 226,[360][361][362][363][364][365] zinccontaining polyoxometalates. 366 polyoxotantalate, [367][368][369][370][371][372][373][374][375][376][377][378][379][380][381][382][383][384] ruthenium-containing polyoxometalates, [385][386][387] coppercontaining polyoxometalates, [388][389][390] chromium-containing polyoxometalates, 391 and polyoxoaurates [392][393][394][395] ; their real applications to substitute their metal oxides counterparts deserve further exploration.…”

“…A number of other transition metal‐based polyoxometalates have been investigated, such as silver‐containing polyoxometalates, zinc‐containing polyoxometalates . polyoxotantalate, ruthenium‐containing polyoxometalates, copper‐containing polyoxometalates, chromium‐containing polyoxometalates, and polyoxoaurates; their real applications to substitute their metal oxides counterparts deserve further exploration.…”