Structure, Stability, and Properties of Boron Encapsulated Complexes of C₆₀, C₅₉B, and C₅₉N

Density functional studies are performed for the boron atom encapsulated complexes of C₆₀, C₅₉B, and C₅₉N using B3LYP and B3LYP-GD2 functionals with 6-311G* basis set. The study shows that the complexes B@C₅₉B and B@C₅₉N can exist in different forms which differ in their structure as well as electronic and magnetic properties. The nature of interaction between the guest and the host is analyzed based on the stabilization energies of complexes for their different spin states. The electronic properties such as vertical electron affinity (VEA), vertical ionization energy (VIE), and energy gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of the complexes are calculated. The transfer of electron spin density and spin-spin coupling of electrons between the guest and the host are examined. The study reveals that ferromagnetic core@shell spin coupling occurs between the host and the guest species of the complexes B@C₅₉B and B@C₅₉N in their triplet state without any transfer of spin density. The values of hyperfine coupling constant (hfcc) for the heteroatom of the cage and for the encapsulated boron atom of the complexes are analyzed, and it indicates that the value of hfcc for the encapsulated boron decreases significantly due to confinement.