The 4-Fe/α-Fe(111) or (211)-surface cluster model of active sites of iron catalysts for ammonia synthesis and the two probable multinuclear coordination modes of dinitro-gen suggested previously were examined by mean...The 4-Fe/α-Fe(111) or (211)-surface cluster model of active sites of iron catalysts for ammonia synthesis and the two probable multinuclear coordination modes of dinitro-gen suggested previously were examined by means of improved cluster-slabbing EHMO calculations. The results are in favor of the suggested model of the active site and the corresponding modes of multinuclear coordination-activation of dinitrogen, and may be used rationally to explain the difference in catalytic activity of ammonia synthesis over the three crystal surfaces, (111), (211) and (100), of α-Fe.展开更多
We have generated one possible active site structure of Oxyhemocyanin (Oxy-Hc) and two possible active site structures of Oxytyrosinase (Oxy-Ty) using the EHMO method. Oxy-Hc active site has a plane configuration, whi...We have generated one possible active site structure of Oxyhemocyanin (Oxy-Hc) and two possible active site structures of Oxytyrosinase (Oxy-Ty) using the EHMO method. Oxy-Hc active site has a plane configuration, while Oxy-Ty has boat configuration. When there exist water molecules, two water molecules are connected with the Oxy-Ty active site weakly. Calculations for the reactions of Oxy-Hc and Oxy-Ty (the water-off) with phenol demonstrate that the former reaction is thermodynamically forbidden, while the latter Is realizable.展开更多
基金Supported by the National Natural Science Foundation of China
文摘The 4-Fe/α-Fe(111) or (211)-surface cluster model of active sites of iron catalysts for ammonia synthesis and the two probable multinuclear coordination modes of dinitro-gen suggested previously were examined by means of improved cluster-slabbing EHMO calculations. The results are in favor of the suggested model of the active site and the corresponding modes of multinuclear coordination-activation of dinitrogen, and may be used rationally to explain the difference in catalytic activity of ammonia synthesis over the three crystal surfaces, (111), (211) and (100), of α-Fe.
文摘We have generated one possible active site structure of Oxyhemocyanin (Oxy-Hc) and two possible active site structures of Oxytyrosinase (Oxy-Ty) using the EHMO method. Oxy-Hc active site has a plane configuration, while Oxy-Ty has boat configuration. When there exist water molecules, two water molecules are connected with the Oxy-Ty active site weakly. Calculations for the reactions of Oxy-Hc and Oxy-Ty (the water-off) with phenol demonstrate that the former reaction is thermodynamically forbidden, while the latter Is realizable.
