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arXiv · 2402.08776

An assessment of frozen natural orbitals and band gaps using equation of motion coupled cluster theory: a case study on polyacene and trans-polyacetylene

Zachary W. Windom·AV Lam·Ajith Perera·Rodney J. Bartlett
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Abstract

Frozen natural orbitals (FNOs) are used to augment IP/EA-EOM-CCSD calculations targeting the band gap of trans-polyacetylene and polyacene. We show the resulting electron affinities (EAs), ionization potentials (IPs), and extrapolated band gaps incur errors that are largely tunable to a desired accuracy, yet require many orders of magnitude fewer core-hours as compared to the corresponding full calculation. The relationship between various FNO truncation schemes and (cc-pV$n$Z) basis set is also examined.

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Zachary W. Windom, AV Lam, Ajith Perera, Rodney J. Bartlett. 2024-02-13. An assessment of frozen natural orbitals and band gaps using equation of motion coupled cluster theory: a case study on polyacene and trans-polyacetylene. https://arxiv.org/abs/2402.08776

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