Optical Gaps of Ionic Materials from GW/BSE-in-DFT and CC2-in-DFT.

ABSTRACT: This work presents a density functional theory (DFT)-based embedding technique for the calculation of optical gaps in ionic solids. The approach partitions the supercell of the ionic solid and embeds a small molecule-like cluster in a periodic environment using a cluster-in-periodic embedding method. The environment is treated with DFT, and its influence on the cluster is captured by a DFT-based embedding potential. The optical gap is estimated as the lowest singlet excitation energy of the embedded cluster, obtained using a wave function theory method: second-order approximate coupled-cluster singles and doubles (CC2), and a many-body perturbation theory method: GW approximation combined with the Bethe-Salpeter equation (GW/BSE). The calculated excitation energies are benchmarked against

SUBMITTER: Sharma M 

PROVIDER: S-EPMC11562370 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature