Classical and ab initio preparation of reliable structures for polymeric coordination compounds

TL;DR

This paper presents a two-step method combining force field optimization and ab initio relaxation to generate reliable structures for polymeric coordination compounds, enabling accurate electronic and magnetic property calculations.

Contribution

The authors introduce a systematic approach for preparing and relaxing structures of polymeric coordination compounds for ab initio studies, improving structural reliability.

Findings

Successful application to Fe(II) triazole compound

Effective relaxation of structures using combined methods

Enhanced accuracy in electronic structure calculations

Abstract

The detailed investigation of electronic and magnetic properties of polymeric coordination materials with accurate ab initio quantum mechanical methods is often computationally extremely demanding because of the large number of atoms in the unit cell. Moreover, usually the available structural data are insufficient or poorly determined, especially when the structure contains hydrogen atoms. In order to be able to perform controlled ab initio calculations on reliable structures, we use a two-step approach to systematically prepare model structures for polymeric coordination compound systems and to relax them to their equilibrium configuration. First, a structure is constructed on the basis of a crystallographic database and optimized by force field methods; in the second step, the structure is relaxed by ab initio quantum mechanical molecular dynamics. With this structure, we perform accurate electronic structure calculations. We will apply this procedure to a Fe(II) triazole compound and to a coordination polymer of Cu(II) ions with 2,5-bis(pyrazol-1-yl)-1,4-dihydroxybenzene.