Excited States from Quasiparticle Hamiltonian Based on Density Functional Theory

Yang Shen; Yichen Fan; Weitao Yang

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arXiv · 2604.27190

Excited States from Quasiparticle Hamiltonian Based on Density Functional Theory

Yang Shen·Yichen Fan·Weitao Yang

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Abstract

Recent advances in occupancy extrapolation (OE) show that potential of orbital-occupation based energy functions can describe electronic excitations. Here, the OE method in the particle-hole channel is extended to an effective quasiparticle Hamiltonian, enabling a multi-configurational description beyond single-determinant OE and $\Delta$SCF. The method performs comparably to the Bethe-Salpeter equation for valence singlet and charge-transfer excitations, and better for valence triplet and Rydberg states, supporting its accuracy and broad applicability.

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Yang Shen, Yichen Fan, Weitao Yang. 2026-04-29. Excited States from Quasiparticle Hamiltonian Based on Density Functional Theory. https://arxiv.org/abs/2604.27190

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