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

Autor:	Marefat Khah A; Quantum Chemistry Group, Ruhr University of Bochum, D-44801 Bochum, Germany., Reinholdt P; Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense, Denmark., Olsen JMH; Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, UiT The Arctic University of Norway, N-9037 Tromsø, Norway., Kongsted J; Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, DK-5230 Odense, Denmark., Hättig C; Quantum Chemistry Group, Ruhr University of Bochum, D-44801 Bochum, Germany.
Jazyk:	angličtina
Zdroj:	Journal of chemical theory and computation [J Chem Theory Comput] 2020 Mar 10; Vol. 16 (3), pp. 1373-1381. Date of Electronic Publication: 2020 Feb 25.
DOI:	10.1021/acs.jctc.9b01162
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.
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu