Deflected spin transmission from radical substituent to Corannulene’s curved surface: Density functional theory calculations

Stable neutral radicals with spherical or curved-surface π-spin networks have drawn much attention in fullerene chemistry and molecule-based magnetism, because their intermolecular magnetic interactions are intrinsically three dimensional. Based on our previous experimental study on an oxoverdazyl radical directly conjugated with corannulene, we have carried out density functional theory calculations for a series of neutral organic π-radicals conjugated with this bowl-shaped hydrocarbon. The unpaired electron spin is delocalized from the radical substituent into the corannulene moiety, showing an uneven spin distribution with spin-rich and spin-poor regions on the curved surface of corannulene. The origin of the characteristic spin distributions was discussed on the basis of a comparison between the spin density distribution of corannulenoxyl having the curved surface structure with that of coronenoxyl bearing a flat surface structure. The magnitude of spin delocalization into the corannulene moiety significantly varies, depending on the radical employed.

Density functional theory calculations for a series of corannulene-based neutral π-radicals have revealed the unevenly distributed spin densities on the curved surface as well as the degree of spin delocalizations. Their electronic structures have been discussed in comparison with that of a coronene-based neutral radical with a flat surface structure.Figure optionsDownload as PowerPoint slide