Describing the electronic structure of molecules in strong magnetic fields

When Coulomb- and magnetic forces compete, our “chemical intuition” about the electronic structure of atoms in molecules is challenged. For example, new bonding mechanisms arise where otherwise unbound systems like the H₂ triplet become bound in a magnetic field perpendicular to the molecular axis.[1] Potential energy surfaces depend strongly on the orientation of the magnetic field and exhibit a plethora of level crossings and avoided crossings which has a strong influence on transition wavelengths and intensities in electronic spectra.

Such strong fields exist for example on magnetic White Dwarf stars. Even though such field strengths are not directly accessible in the lab, strong field-effects can be encountered on Earth in cases where the Coulomb interaction is damped as for example in Rydberg states or semi-conductors.

In this contribution, we discuss the influence of the magnetic field on the electronic structure of atoms and molecules and present pitfalls and recent methodological developments for their accurate description.[4,5] In addition, we present a first assignment of a metal-containing spectrum from a strongly magnetized White Dwarf.[6]

1. K. K. Lange, E. I. Tellgren, M. R. Hoffmann, T. Helgaker, Science 337, 327 (2012)

2. F. Hampe and S. Stopkowicz, J. Chem. Theory Comput. 15, 4036 (2019)

3. F. Hampe, N. Gross, and S. Stopkowicz, Phys. Chem. Chem. Phys. 22, 23522 (2020)

4. S. Blaschke and S. Stopkowicz, J. Chem. Phys., 156, 044115 (2022)

5. M.-P. Kitsaras, L. Grazioli, Blaschke, and S. Stopkowicz, in prep. 2022

6. M. Hollands, S. Stopkowicz, M.-P. Kitsaras, S. Blaschke, J.J. Hermes, submitted (2022)