Accurate Quasiparticle Spectra from the T-Matrix Self-Energy and the Particle-Particle Random Phase Approximation

Du Zhang; Neil Qiang Su; Weitao Yang

doi:10.1021/acs.jpclett.7b01275

Accurate Quasiparticle Spectra from the T-Matrix Self-Energy and the Particle-Particle Random Phase Approximation

J Phys Chem Lett. 2017 Jul 20;8(14):3223-3227. doi: 10.1021/acs.jpclett.7b01275. Epub 2017 Jul 3.

Authors

Du Zhang¹, Neil Qiang Su¹, Weitao Yang^{1

2}

Affiliations

¹ Department of Chemistry, Duke University , Durham, North Carolina 27708, United States.
² Key Laboratory of Theoretical Chemistry of Environment, School of Chemistry and Environment, South China Normal University , Guangzhou 510006, China.

PMID: 28654275
DOI: 10.1021/acs.jpclett.7b01275

Abstract

The GW self-energy, especially G₀W₀ based on the particle-hole random phase approximation (phRPA), is widely used to study quasiparticle (QP) energies. Motivated by the desirable features of the particle-particle (pp) RPA compared to the conventional phRPA, we explore the pp counterpart of GW, that is, the T-matrix self-energy, formulated with the eigenvectors and eigenvalues of the ppRPA matrix. We demonstrate the accuracy of the T-matrix method for molecular QP energies, highlighting the importance of the pp channel for calculating QP spectra.