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arXiv · 2406.14716

Exploring electron affinities, LUMO energies, and band gaps with electron-pair theories

Marta Gałyńska·Paweł Tecmer·Katharina Bogusławski
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Abstract

We introduce the electron attachment equation-of-motion pair coupled cluster doubles (EA-EOM-pCCD) ansatz, which allows us to inexpensively compute electron affinities, energies of unoccupied orbitals, and electron attachment spectra. We assess the accuracy of EA-EOM-pCCD for a representative data set of organic molecules for which experimental data is available, as well as the electron attachment process in uranyl dichloride. EA-EOM-pCCD provides more reliable energies for the LUMO than its ionization potential EOM counterpart for the HOMO. The advantage of EA-EOM-pCCD is demonstrated for rylene and rylene diimide units of different chain lengths, where the differences between theoretical and experimental EAs approach chemical accuracy.

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Marta Gałyńska, Paweł Tecmer, Katharina Bogusławski. 2024-06-20. Exploring electron affinities, LUMO energies, and band gaps with electron-pair theories. https://doi.org/10.1021/acs.jpca.4c06904

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