The geometry of C~3~6(D~6~h symmetry) is optimized at the B3LYP/6- 31G^*, B3LYP/6-311+G^* levels using DFT approaches. The characteristics of geometric structure and electronic structure are discussed; To discuss the influence of Li, Na, K, in C~3~6, B3LYP/6- 31G^* level is used to investigate the equilibrium geometries of Li@C~3~6, Na@C~3~6, K@C~3~6; The single point energies of C~3~6H~6, C~3~6H~1~2, X@C~3~6(X=H, Li, Na, K) at the B3LYP/6-311+G^* level are also calculated.

Key words: ELECTRONIC STRUCTURE, MOLECULAR CONFIGURATION, FULLERENES