Chiral Jahn-Teller Distortion in Quasi-Planar Boron Clusters

Helical (frontier) molecular orbitals [Chem. Sci. 2013, 4, 4278] were reported a decade ago, but helical molecular spin densities [Mol. Phys. 2022, e2157774] have been observed by us only very recently. In this work, we have observed that some chiral boron clusters ( B 16 – , B 20 – , B 24 – , and B 28 – ) can simultaneously have helical molecular orbitals and helical spin densities; these seem to be the first compounds discovered to have this intriguing property. We show that chiral Jahn-Teller distortion of quasi-planar boron clusters drives the formation of the helical molecular spin densities in these clusters and show that elongation/enhancement of helical molecular orbitals can be achieved by simply adding more building blocks via a linker. Aromaticity of these boron clusters is discussed. Chiral boron clusters may find potential applications in spintronics, such as molecular magnets.