摘要
The singlet state potential energy curve of the reaction: Ni (d1 0 1S)+ CH 4 → NiCH 2 + H 2, and geometric structures and vibrational frequencies of all intermediates and transition states in the reaction path were studied by B3LYP method. In the reaction, an atom molecule complex NiCH 4 acting as precursor in the breaking of C-H bond was predicted. For NiCH 4, a frequency of 2988 cm -1 is typical of methane molecularly adsorbed on Ni. A nickel hydrido methyl complex HNiCH 3 is formed upon the very low barrier insertion of Ni 0 into a C-H bond of CH 4. A dihydrogen complex of atom nickel carbene (H 2)NiCH 2 proceeds from the migration of α hydrogen from carbon to metal with considerably large barrier, indicating that this is the rate determining step in the whole reaction. In general, the overall reaction is mildly exothermic by 1.6 kJ·mol -1 relative to Ni(d1 0 1S) + CH 4 reactants.
The singlet state potential energy curve of the reaction: Ni (d1 0 1S)+ CH 4 → NiCH 2 + H 2, and geometric structures and vibrational frequencies of all intermediates and transition states in the reaction path were studied by B3LYP method. In the reaction, an atom molecule complex NiCH 4 acting as precursor in the breaking of C-H bond was predicted. For NiCH 4, a frequency of 2988 cm -1 is typical of methane molecularly adsorbed on Ni. A nickel hydrido methyl complex HNiCH 3 is formed upon the very low barrier insertion of Ni 0 into a C-H bond of CH 4. A dihydrogen complex of atom nickel carbene (H 2)NiCH 2 proceeds from the migration of α hydrogen from carbon to metal with considerably large barrier, indicating that this is the rate determining step in the whole reaction. In general, the overall reaction is mildly exothermic by 1.6 kJ·mol -1 relative to Ni(d1 0 1S) + CH 4 reactants.
出处
《四川大学学报（自然科学版）》
CAS
CSCD
北大核心
2001年第4期605-608,共4页
Journal of Sichuan University(Natural Science Edition)
基金
国家自然科学基金 (No .2 98730 2 8)
国家重点基础研究发展规划基金 (973
No .G19990 2 2 40 7)
教育部博士点专项 (No .2 0 0 0 0 6 10 2 8)
四川省应用基础研究基金 (No .2 0 0 0 18 16 )
