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arXiv · 2008.03610

Ground and Excited State First-Order Properties in Many-Body Expanded Full Configuration Interaction Theory

Janus J. Eriksen·Jürgen Gauss
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Abstract

The recently proposed many-body expanded full configuration interaction (MBE-FCI) method is extended to excited states and static first-order properties different from total, ground state correlation energies. Results are presented for excitation energies and (transition) dipole moments of two prototypical, heteronuclear diatomics---LiH and MgO---in augmented correlation consistent basis sets of up to quadruple-$\zeta$ quality. Given that MBE-FCI properties are evaluated without recourse to a sampled wave function and the storage of corresponding reduced density matrices, the memory overhead associated with the calculation of general first-order properties only scales with the dimension of the desired property. In combination with the demonstrated performance, the present developments are bound to admit a wide range of future applications by means of many-body expanded treatments of electron correlation.

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Janus J. Eriksen, Jürgen Gauss. 2020-08-08. Ground and Excited State First-Order Properties in Many-Body Expanded Full Configuration Interaction Theory. https://doi.org/10.1063/5.0024791

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