He and N encapsulations in small cages: model computations for possible nanotechnology systems

Endohedral cage compounds have been considered as possible candidate species for molecular memories. In this report, computations are carried out on four hypothetical He-containing endohedral systems, He@C14H16 (isogarudane and garudane cages) and He@C36 (D6h and D2d cages), and two hypothetical N-containing endohedral systems, N@C36 (D6h and D2d cages). Geometry optimizations are followed by vibrational analysis in some cases. The geometry optimizations can indeed produce local energy minima for the endohedral systems. While in N@C36 D6h the nitrogen atom has a central location, in N@C36 D2d it exhibits a bonding pattern. Thermodynamic and kinetic stability aspects are also discussed.