Structure and Stability of Endohedral X@C60F, X@C60F2 (X = N, H), and (H@C60)2

The structure and stability of endohedral X@C60Fn (X = N, H; n = 1, 2) and (H@C-60)(2) are computed at the B3LYP level of density functional theory. The most stable N@C60F has one endo N C bond, while N@C60F2 favors nitrogen atom at the cage center. Both H@C60F and H@C60F2 favor isomers with one endo C H bond. The most stable dimer structure, (H@C-60)(2), has one intercage C-C bond and two endo C-H bonds, and is stable below 650 K, but dissociates above 650 K.