Work

The application of Dyall Hamiltonian-based MRPT2 in high-lying electronically excited state calculations

Year: 2025

Type: article

Abstract: As the MRPT2 methods based on the Dyall Hamiltonian, the MS-NEVPT2 and SDSPT2 are both robust to calculate low-lying excited states of strongly correlated systems without intruder state problem (ISP). However, their applicability to high-lying excited states remains underexplored in detail. To address this, we systematically evaluated 30 electronic states across 21 organic molecules using MS-NEVPT2 and SDSPT2. Our analysis confirms that both methods effectively mitigate the ISP and achieve reasonably vertical excitation energies when appropriate level shift parameters are applied. This comprehensive study establishes essential theoretical references for modeling high-lying excited states in molecular systems using MS-NEVPT2 and SDSPT2.

Source: Chemical Physics Letters

DOI: 10.1016/j.cplett.2025.142096

Authors: Yiyao Li, Shengnan Luo, Panfeng Wu, Yibo Lei

Institutions: Xi'an Shiyou University, Northwest University

Language: English

Topic: Advanced Chemical Physics Studies

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,270

Funder: National Natural Science Foundation of China