QM/MM calculations assist the development of a robust shell-model interatomic potential for CeO2

Home » QM/MM calculations assist the development of a robust shell-model interatomic potential for CeO2

QM/MM calculations assist the development of a robust shell-model interatomic potential for CeO2

Feb 13, 2023

Xingfan Zhang, University College London

Polarisable shell-model potentials are widely used for modelling charged defects in solids. However, at the pure molecular mechanics (MM) level of theory, the calculated defect energetics may not satisfy the requirement of quantitative predictions and are limited to only certain charged states.

An illustration of Mott-Littleton and QM/MM models of CeO2 used in the development of a novel interatomic potential.

We proposed a novel strategy that employs accurate ionic polarisabilities, defect structures, and formation energies calculated by the QM/MM embedded-cluster approach in developing a shell-model potential for CeO2. The new potential not only reproduces a wide range of physical properties of CeO2, but also unifies the predictions of all relevant charged defects based on the Mott–Littleton approach and QM/MM electronic-structure calculations. These findings provide opportunities for accurate large-scale modelling of the partial reduction and non-stoichiometry in CeO2, as well as a prototype for developing robust interatomic potentials for other defective crystals.

 

Citation:
X. Zhang, L. Zhu, Q. Hou, J. Guan, Y. Lu, T. W. Keal, J. Buckeridge, C. R. A. Catlow and A. A. Sokol, “Toward a Consistent Prediction of Defect Chemistry in CeO2”, Chem. Mater., 2023, 35, 1, 207–227. DOI: 10.1021/acs.chemmater.2c03019