MINDO/3方法是Dewar等人提出的一系列改进的INDO方法之一,也是该系列方法中最成功的方案。它能同时获得较好的几何构型和生成热,且所用机时少。因此该法适于研究大分子几何优化及反应过渡态问题。 用解析方法求出能量一阶导数(即能量梯度),是近年来研究化学反应和过渡态的方便手段。对于ZDO近似的SCF方法,使用梯度方法更有其优越性。从而,可用 The MINDO / 3 method is one of a series of improved INDO methods proposed by Dewar et al. And is also the most successful solution in this series of methods. It can achieve better geometry and generate heat at the same time, and the use of less time. Therefore, this method is suitable for studying the optimization of macromolecules and the reaction transition state. Using analytic methods to derive the first derivative of energy (ie, the energy gradient) is a convenient means of studying chemical reactions and transition states in recent years. For the ZDO approximation of the SCF method, the use of gradient method has its advantages. Thus, available