The GW/BSE Method in Magnetic Fields

The GW approximation and the Bethe-Salpeter equation have been implemented into the Turbomole program package for computations of molecular systems in a strong, finite magnetic field. Complex-valued London orbitals are used as basis functions to ensure gauge-invariant computational results. The implementation has been benchmarked against triplet excitation energies of 36 small to medium-sized molecules against reference values obtained at the approximate coupled-cluster level (CC2 approximation). Finally, a spectacular change of colour from orange to green of the tetracene molecule is induced by applying magnetic fields between 0 and 9,000 T perpendicular to the molecular plane.

Automated summary

The GW approximation and the Bethe-Salpeter equation have been successfully implemented in the Turbomole program package for computations of molecular systems in a strong magnetic field. Complex-valued London orbitals are used as basis functions to ensure gauge-invariant computational results. Benchmarking against triplet excitation energies of 36 small to medium-sized molecules validated the accuracy of the implementation. Additionally, the tetracene molecule exhibits a dramatic color change from orange to green when subjected to magnetic fields ranging from 0 to 9,000 T perpendicular to the molecular plane.