Avoiding Electron Spill-Out in QM/MM Calculations on Excited States with Simple Pseudopotentials

Alireza Marefat Khah*, Peter Reinholdt, Jógvan Magnus Haugaard Olsen, Jacob Kongsted, Christof Hättig

*Kontaktforfatter for dette arbejde

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

Abstrakt

QM/MM calculations of electronic excitations with diffuse basis sets often have large errors due to spill-out of electrons from the quantum subsystem. The Pauli repulsion of the electrons by the environment has to be included to avoid this. We propose transferable atomic all-electron pseudopotentials that can readily be combined with most MM force fields to avoid electron spill-out. QM/MM excitation energies computed with time-dependent Hartree-Fock and the algebraic diagrammatic construction through second-order are benchmarked against supermolecular calculations to validate these new pseudopotentials. The QM/MM calculations with pseudopotentials give accurate results that are stable with augmentation of the basis set with diffuse functions. We show that the largest contribution to residual deviations from full QM calculations is caused by the missing London dispersion interaction.

OriginalsprogEngelsk
TidsskriftJournal of Chemical theory and Computation
Vol/bind16
Udgave nummer3
Sider (fra-til)1373-1381
ISSN1549-9618
DOI
StatusUdgivet - 2020

Fingeraftryk Dyk ned i forskningsemnerne om 'Avoiding Electron Spill-Out in QM/MM Calculations on Excited States with Simple Pseudopotentials'. Sammen danner de et unikt fingeraftryk.

Citationsformater