Hyperfine structure of Sc@C82 from ESR and DFT.

The electron spin g- and hyperfine tensors of the endohedral metallofullereneSc@C82 are anisotropic. Using electron spin resonance (ESR) and density functional theory (DFT),we can relate their principal axes to the coordinate frame of the molecule, finding that theg-tensor is not axially symmetric. The Sc bond with the cage is partlycovalent and partly ionic. Most of the electron spin density is distributedaround the carbon cage, but 5% is associated with the scandiumdyz orbital, and this drives the observed anisotropy. [ABSTRACT FROM AUTHOR]