regional embedding enables high level quantum chemistry for surface science

• DOI: 10.48550/arxiv.2010.00527
• Publication Date: 2021-01-21
• Authors: Bryan T. G. Lau; Gerald Knizia; Timothy C. Berkel...
• Keywords: focal-point corrections; Regional Embedding Enables High-Lev.; overlap criterion; Biophysics; FOS: Physical sciences; CCSD; 01 natural sciences; ab initio wave function methods; modeling adsorbates; Sociology; Physics - Chemical Physics; 0103 physical sciences; Surface Science; fragment sizes; adsorption energies; Chemical Physics (physics.chem-ph); wave function methods; Condensed Matter - Materials Science; translational symmetry; Materials Science (cond-mat.mtrl-sci); embedding approach; 541; wave function treatments; lithium hydride; boron nitride; density functionals; graphene substrates show; Medicine; target fragment; Physical Sciences not elsewhere classified

Compared to common density functionals, ab initio wave function methods can provide greater reliability and accuracy, which could prove useful when modeling adsorbates or defects of otherwise periodic systems. However, the breaking of translational symmetry necessitates large supercells that are often prohibitive for correlated wave function methods. As an alternative, we introduce the regional embedding approach, which enables correlated wave function treatments of only a target fragment of interest through small, fragment-localized orbital spaces constructed using a simple overlap criterion. Applications to the adsorption of water on lithium hydride, hexagonal boron nitride, and graphene substrates show that regional embedding combined with focal point corrections can provide converged CCSD(T) (coupled cluster) adsorption energies with very small fragment sizes.