Work

State-Interaction Approach for g-Matrix Calculations in TDDFT: Ground-Excited State Couplings and beyond First-Order Spin–Orbit Effects

Year: 2025

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide We introduce a state-interaction approach for computing g -matrices within time-dependent density functional theory (TDDFT) and the Tamm–Dancoff approximation (TDA), applied here for the first time. This method provides a detailed understanding of g -shifts by explicitly accounting for spin–orbit couplings (SOC) and excitation energies, enabling the analysis of different SOC orders and their contributions. To evaluate its accuracy and reliability, we compare state-interaction TDDFT and TDA with the widely used one-component coupled-perturbed Kohn–Sham approach. Applications to a diverse set of systems, including light and heavy atom molecules as well as transition-metal complexes, demonstrate that both methods yield comparable results in the absence of heavy elements, while the state-interaction approach offers improved insights into SOC effects and their impact on g -shifts.

Source: Journal of Chemical Theory and Computation

DOI: 10.1021/acs.jctc.5c00514

Authors: Antonio Cebreiro-Gallardo, David Casanova

Institutions: University of the Basque Country, Donostia International Physics Center, Ikerbasque

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: $4,500