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arXiv · 1505.08045

Coupled-cluster theory for atoms and molecules in strong magnetic fields

Stella Stopkowicz·Jürgen Gauss·Kai K. Lange·Erik I. Tellgren·Trygve Helgaker
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Abstract

An implementation of coupled-cluster (CC) theory to treat atoms and molecules in finite magnetic fields is presented. The main challenges stem from the magnetic-field dependence in the Hamiltonian, or, more precisely, the appearance of the angular momentum operator, due to which the wave function becomes complex and which introduces a gauge-origin dependence. For this reason, an implementation of a complex CC code is required together with the use of gauge-including atomic orbitals to ensure gauge-origin independence. Results of coupled-cluster singles--doubles--perturbative-triples (CCSD(T)) calculations are presented for atoms and molecules with a focus on the dependence of correlation and binding energies on the magnetic field.

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Stella Stopkowicz, Jürgen Gauss, Kai K. Lange, Erik I. Tellgren, Trygve Helgaker. 2015-08-12. Coupled-cluster theory for atoms and molecules in strong magnetic fields. https://doi.org/10.1063/1.4928056

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