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arXiv · 1805.06436

New generation of effective core potentials from correlated calculations: 3d transition metal series

Abdulgani Annaberdiyev·Guangming Wang·Cody A. Melton·M. Chandler Bennett·Luke Shulenburger·Lubos Mitas
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Abstract

Recently, we have introduced a new generation of effective core potentials (ECPs) designed for accurate correlated calculations but equally useful for a broad variety of approaches. The guiding principle has been the isospectrality of all-electron and ECP Hamiltonians for a subset of valence many-body states using correlated, nearly-exact calculations. Here we present such ECPs for the 3d transition series Sc to Zn with Ne-core, i.e, with semi-core 3s and 3p electrons in the valence space. Besides genuine many-body accuracy, the operators are simple, being represented by a few gaussians per symmetry channel with resulting potentials that are bounded everywhere. The transferability is checked on selected molecular systems over a range of geometries. The ECPs show a high overall accuracy with valence spectral discrepancies typically $\approx$ 0.01-0.02 eV or better. They also reproduce binding curves of hydride and oxide molecules typically within 0.02-0.03 eV deviations over the full non-dissociation range of interatomic distances.

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Abdulgani Annaberdiyev, Guangming Wang, Cody A. Melton, M. Chandler Bennett, Luke Shulenburger, Lubos Mitas. 2018-05-16. New generation of effective core potentials from correlated calculations: 3d transition metal series. https://doi.org/10.1063/1.5040472

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