Surprisingly Large Electronic g-Factors in p-Doped Lead Clusters

A Magnetic Molecular Beam Deflection Study Coupled with Modern Quantum Chemistry


Molecular Magnetism is a thriving field of research with remarkable discoveries being made with single-molecule magnets where d- and f-block elements serve as paramagnetic centers. Tetrel clusters p-doped with elements of the triel group also state magnetically highly relevant systems. If lead is chosen as tetrel cage element, the endohedral clusters are found to exhibit peculiar spin-orbit coupling effects with strongly impacted electronic g-factors.

It is reported on huge electronic g-factors of g=3.5-4.0 which were experimentally observed for the endohedral clusters AlPb12 and InPb12 and are so far unreached by molecules solely based on main group elements as well as most single-ion magnets of high symmetry. In contrast, GaPb12 surprisingly possesses a g-factor of less than 2.0. This tunable behavior is investigated further by constructing a qualitative model based on perturbation theory and by performing multireference ab initio calculcations.

The large g-factors are found to be a consequence of a particularly strong spin-orbit coupling in conjunction with a pyritohedral molecular symmetry. Contrarily, the g-factor in GaPb12 is quenched due to a Ga s orbital ground state that is subject to the d-block contraction resulting in an icosahedral symmetry. The results do not only disclose a deep understanding of the electronic structure, but also provide an insight into the fascinating interplay of metal dopant and tetrel ligands being of fundamental relevance in molecular magnetism.

Link to Publication

Link to HPC Project