【摘要】 采用B3LYP方法对N、H、C、O使用6-311++G(d,p)基组,对Ti使用LANL2DZ赝势基组,研究计算1(TiO2)n(n=1～3)催化水解HNCO的微观反应机制。研究HNCO和H2O在1(TiO2)n上的不同进攻方式。为了考察催化剂对反应的影响,研究了在没有催化剂作用下的HNCO+H2O的微观反应机制。结果表明:无催化剂条件下反应的发生需要克服活化能158.20 kJ/mol。1(TiO2)n对反应有着良好的催化效果,显著降低了反应的活化能垒,使反应能够在温和的条件下进行。H2O优先进攻催化剂的方式是能量上有利的过程,与实验结果吻合。更多还原

【Abstract】 The reaction mechanism of HNCO and H2O catalyzed by 1(TiO2)n(n=1-3) was investigated.The properties of non-covalent interactions in intermediates and transition states with weak bond were obtained by using standardized 6-311++G(d,p) for carbon,oxygen,hydrogen,and nitrogen atoms and the effective core potential(ECP) of Hay and Wadt with a double-ζ basis set(LANL2DZ) for Ti using B3LYP method.The different attack modes of HNCO and H2O on 1(TiO2)n(n=1-3) were explored,and the reaction mechanism of HNCO+H2O without any catalyst was also investigated to examine the effect of 1(TiO2)n catalysts on the HNCO hydrolysis reaction.The results demonstrated that the reaction HNCO+H2O should overcome the highest activity energy of 158.20 kJ/mol if there was no catalyst.1(TiO2)n was active for the hydrolysis of the isocyanic acid and lowered the activity barrier in the process.The catalytic reaction could take place at a lower temperature.The first attack of H2O on the catalyst was energetically favorable,which was consistent with the experimental results.更多还原