The solid transition - metal cluster compounds M2B (M= Mo, W) and M2Ni (M= Zr, Hf) with Al2Cu structure type and MGe2 (M = Nb, Ta) with CrSi2 structure type become superconductors under low temperatures.

• Al_2Cu型和CrSi_2型固相过渡金属原子簇化合物M_2B(M=Mo；W)；M_2Ni(M=Zr；Hf)和MGe_2(M=Nb；Ta)在低温下出现超导行为.