Electron rich of M: dihydride Electron poor of M: dihydrogen complex Explain: Mo(CO)3PMe3)H2 dihydride(两个分离的H) Mo(CO)2(PMe33(H2) dihydrogen complexElectron rich of M: dihydride Electron poor of M: dihydrogen complex Explain: Mo(CO)3 (PMe3 )H2 dihydride ( 两个分离的H) Mo(CO)2 (PMe3 )3 (H2 ) dihydrogen complex