[HTML][HTML] Rationale for the extrapolation procedure in selected configuration interaction

HGA Burton, PF Loos - The Journal of Chemical Physics, 2024 - pubs.aip.org
Selected configuration interaction (SCI) methods have emerged as state-of-the-art
methodologies for achieving high accuracy and generating benchmark reference data for …

Can GW handle multireference systems?

A Ammar, A Marie, M Rodríguez-Mayorga… - The Journal of …, 2024 - pubs.aip.org
Due to the infinite summation of bubble diagrams, the GW approximation of Green's function
perturbation theory has proven particularly effective in the weak correlation regime, where …

A regularized second-order correlation method from Green's function theory

CJN Coveney, DP Tew - Journal of Chemical Theory and …, 2023 - ACS Publications
We present a scalable single-particle framework to treat electronic correlation in molecules
and materials motivated by Green's function theory. We derive a size-extensive Brillouin …

[HTML][HTML] Unphysical discontinuities, intruder states and regularization in GW methods

E Monino, PF Loos - The Journal of Chemical Physics, 2022 - pubs.aip.org
By recasting the non-linear frequency-dependent GW quasiparticle equation into a linear
eigenvalue problem, we explain the appearance of multiple solutions and unphysical …

Accurate full configuration interaction correlation energy estimates for five-and six-membered rings

Y Damour, M Véril, F Kossoski, M Caffarel… - The Journal of …, 2021 - pubs.aip.org
Following our recent work on the benzene molecule [P.-F. Loos, Y. Damour, and A.
Scemama, J. Chem. Phys. 153, 176101 (2020)], motivated by the blind challenge of Eriksen …

General properties of fidelity in non-Hermitian quantum systems with PT symmetry

YT Tu, I Jang, PY Chang, YC Tzeng - arxiv preprint arxiv:2203.01834, 2022 - arxiv.org
The fidelity susceptibility is a tool for studying quantum phase transitions in the Hermitian
condensed matter systems. Recently, it has been generalized with the biorthogonal basis for …

Noncovalent interactions from models for the Møller–Plesset adiabatic connection

KJ Daas, E Fabiano, F Della Sala… - The journal of …, 2021 - ACS Publications
Given the omnipresence of noncovalent interactions (NCIs), their accurate simulations are of
crucial importance across various scientific disciplines. Here we construct accurate models …

Symmetry protected exceptional points of interacting fermions

R Schäfer, JC Budich, DJ Luitz - Physical Review Research, 2022 - APS
Non-Hermitian quantum systems can exhibit spectral degeneracies known as exceptional
points, where two or more eigenvectors coalesce, leading to a nondiagonalizable Jordan …

Benchmarking CASPT3 vertical excitation energies

M Boggio-Pasqua, D Jacquemin… - The Journal of Chemical …, 2022 - pubs.aip.org
Based on 280 reference vertical transition energies of various excited states (singlet, triplet,
valence, Rydberg, n→ π*, π→ π*, and double excitations) extracted from the QUEST …

More quantum chemistry with fewer qubits

J Günther, A Baiardi, M Reiher, M Christandl - Physical Review Research, 2024 - APS
Quantum computation is one of the most promising new paradigms for the simulation of
physical systems composed of electrons and atomic nuclei, with applications in chemistry …