The geometric configurations, electronic structures and vibrational frequencies of the Ga_mN (m=1～9) clusters were calculated with B3LYP method at 6-31G* level. It is found that the stabilities of the Ga_mN are closely related with the numbers of the two kinds of bond type. The secondary energy differences of the ground states reveal that the Ga_mN clusters with even m are more stable than those with odd m.

Key words: Ga_mN cluster, density functional theory, ground state structure, stability