双原子分子内氛重组能的Ab Initio-Morse函数研究

基于重组织现象的自交换模型,提出一种内氛重组能精确的Morse函数标度方案,并对气相电子转移过程中双原子分子体系进行了计算,给出了反应物的结构重组织指标。在HFSCF水平上利用四种基组(6-31G^*、6-31GE、DZ和DZP(d))对标度中所含参数进行了计算,并与实验结果进行比较.结果表明,ab initio计算与实验标度值吻合较好,误差在±1.skcal/mol以内。该方法不仅改进了经典模型而且避免了获得有效的实验数据的困难,给出了一种精确地计算气相电子转移过程中双原子分子内氛重组能的ab initio算法。

AB INITIO-MORSE FUNCTION STUDY ON INNER-SPHERE REORGANIZATION ENERGY OF MOLECULE AB IN GASEOUS ELECTRON TRANSFER PROCESS

The inner-sphere reorganization energies (REs) of diatondc molecules in gaseous phase electron transfer (ET)process have been calculated in terms of Morse function scale model presented in this paper, the struCtural reorganization index (activated radius of the reduCed molecule) is given, the parameters involved can be determined via ah initio calculations at HFSCF levels (6-31G, 6-31G^*, DZ and DZP (d)), The inner-sphere RE values are calibrated by comparing molecular structural parameters (bond dissociation energies, force constants) with experimental data. Results indicate that ah initio calculation values are better agreement with experimental ones, and are found to be accurate to within + l.5kcal/mol or better. This method not only improves classical model but also gets around the difficulties in obtaining available experimental data and constitutes an accurate ah initio method in calculating inner-sphere REs of diatondc molecules in gaseous ET process.