Probing the electronic structures and properties of neutral and charged arsenic sulfides (AsnS(−1,0,+1), n = 1–7) using Gaussian-3 theory.

The structures and energies of neutral and charged arsenic sulfides As _nS ^(−1,0,+1) ( n = 1–7) were systematically investigated using the G3 method. The bonding properties and the stabilities of As _nS and their ions were discussed. The adiabatic electron affinities (AEAs) and adiabatic ionization potentials (AIPs) were presented. The ground-state structures of As _nS can be considered as the lowest-energy structure of neutral As _n+1 by replacing an As atom with a S atom, that is, “substitutional structure”, in which the feature of sulfur bonding is edge-bridging. The ground-state structures of As _nS ⁺ tend to be derived from the lowest-energy structure of cation As _n⁺ by attaching to a S atom, that is, “attaching structure”, in which the sulfur can be three-fold coordinated. There is no rule to be found for the ground-state structure of anion As _nS ⁻, in which the sulfur can be a terminal atom. There are odd-even alternations in both AEAs and AIPs as a function of size of As _nS. The dissociation energies of S, S ⁻, and/or S ⁺ from neutral As _nS and their ions were calculated to examine their stabilities. [ABSTRACT FROM AUTHOR]