Quasiparticle band structure of infinite hydrogen fluoride and hydrogen chloride chains

TL;DR

This study investigates the quasiparticle band structures of infinite hydrogen fluoride and hydrogen chloride chains using advanced Green's function methods, revealing electron correlation effects that significantly shift energy levels without altering bandwidth.

Contribution

It applies local molecular orbital and crystal orbital ADC methods to model electron correlations in infinite chains, a novel approach for these materials.

Findings

Electron correlations cause significant energy level shifts.

Bandwidth remains largely unchanged despite correlations.

Nearest-neighbor interactions suffice for accurate correlation calculations.

Abstract

We study the quasiparticle band structure of isolated, infinite HF and HCl bent (zigzag) chains and examine the effect of the crystal field on the energy levels of the constituent monomers. The chains are one of the simplest but realistic models of the corresponding three-dimensional crystalline solids. To describe the isolated monomers and the chains, we set out from the Hartree-Fock approximation, harnessing the advanced Green's function methods "local molecular orbital algebraic diagrammatic construction" (ADC) scheme and "local crystal orbital ADC" (CO-ADC) in a strict second order approximation, ADC(2,2) and CO-ADC(2,2), respectively, to account for electron correlations. The configuration space of the periodic correlation calculations is found to converge rapidly only requiring nearest-neighbor contributions to be regarded. Although electron correlations cause a pronounced shift of the quasiparticle band structure of the chains with respect to the Hartree-Fock result, the bandwidth essentially remains unaltered in contrast to, e.g., covalently bound compounds.