【摘要】 使用密度泛函 (DFT)方法对Si(NCO) +2 的可能异构体进行了计算研究 ,在UB3LYP/ 6-3 1 1G(d)理论级别下得到了 6种异构体的能量和振动频率 .结果表明 ,以 2个NCO基团直接与Si+配位形成的异构体最为稳定 .理论计算得到一个以 2个CO分子对称方式吸附于SiN2 +两侧而形成的络合物 ,这个络合物是否存在需进一步证实 .在UB3LYP/ 6-3 1 1G (d) +Ez 级别下 ,反应Si++ 2NCO→Si(NCO) +2 的焓变为 -751 94kJ/mol,说明此反应在能量上相当有利 .更多还原

【Abstract】 The isomers of Si(NCO) + 2 molecular ion were investigated using density functional theory at UB3LYP/6-311G(d) level of theory. Six isomers and their energies and vibrational frequencies were gained. The results showed that the isomers that were formed by two NCO radicals coordinating directly with Si + are the most stable. There is a complex that is formed by two CO molecules absorbing with SiN + 2 molecular. The complex need be confirmed by more studies for large spin contamination. The reaction enthalpy of Si ++2NCO→Si(NCO) + 2 is -751.94 kJ/mol at UB3LYP/6-311G(d)+ E z level of theory, and the energy is favorable for the reaction.更多还原