共轭烯烃的分子几何构型、电子结构和生成热的DMM和AM1、PM3的比较研究

DMM and AM1, PM3 Studies of the Geometries, Electronic Structures and Heats of Formation of Ten Conjugated Hydrocarbons

运用Ｄｅｌｆｔ分子力学（ＤＭＭ）力场和程序以及半经验分子轨道ＡＭ１和ＰＭ３方法计算研究了丁二烯、苯、甲苯、联苯、苯乙烯、富烯、、环辛四烯、［２，２］对环烷和菲等１０个共轭烯烃分子的几何构型、电子结构和生成热．ＤＭＭ计算的几何构型和生成热与实验结果相吻合，电荷分布结果与从头计算结果较接近．ＡＭ１和ＰＭ３计算的几何构型较好，但计算的生成热与实验结果偏差较大．ＰＭ３计算值比ＡＭ１的稍好．

The Delft molecular mechanics(DMM) force field and program and the semi empirical molecular orbital AM1 and PM3 methods have been employed to study the geometries, electronical structures and heats of formation of ten conjugated hydrocarbons. The geometries and heats of formation calculated by DMM are in good agreement with experimental results, and DMM computed atomic charges are close to that of ab initio calculations. The geometries obtained by AM1 and PM3 are good, but the heats of formation are largely deviated from the experimental data. PM3 results are comparatively better than that of AM1.