【摘要】 提出了一种经济实用的价键计算方法 VB-MP2方法 .将体系的电子分为非活性电子和活性电子 ,应用 MP2方法计算非活性电子的相关能效应 ,用 VB方法处理活性电子 .测试计算表明 ,该方法保持了价键方法的特点 ,且计算结果比传统的使用芯 -价分离技术的价键方法有较大的改善 .更多还原

【Abstract】 A practical valence bond method, called VB-MP2, is presented. The method combines valence bond method and many-body perturbation theory by using MP2 method to get the electronic correlation of inactive electrons. The bond energies of some molecules, such as F 2, Cl 2, Br 2, CH 3Li \%etc\%., are computed by using the VB-MP2 method. Testing calculations show that VB-MP2 method has the qualities of a VB method along with a quantitative advantage over VB-only method in comparison with traditional core-valence separation.更多还原