关于HF,F_2,FCl,FBr的分子形貌轮廓以及边界电子密度的研究

Study on molecular intrinsic characteristic contour and the boundary electron density about HF,F_2,FCl and FBr

利用Davidson等人发展多年的MELD精密从头计算程序的CISD方法,结合自编的分子形貌程序,描绘HF,F2,FCl,FBr双原子分子形貌图.计算双原子分子中X原子端和F原子端在垂直于化学键方向上和沿着化学键方向上的分子形貌轮廓参数R(R/a.u.)以及对应的边界电子密度ED(ED/10-3a.u.).比较各原子端轮廓参数与相应孤立原子半径的大小,联系第一电离能的变化趋势,发现对于卤族元素之间形成的氟化物,第一电离能越小,分子形貌轮廓参数越大,边界电子密度越小.对于核电荷数相同的两个原子形成的氟化物,无论垂直于化学键方向还是沿着化学键方向上的分子形貌轮廓参数和对应的边界电子密度都呈现对称关系.对于HF,F2,FCl,FBr双原子分子形貌的研究,为我们进一步讨论其他双原子分子的性质和特征,提供了有效可靠的方法.

The paper mainly studies the molecular face of HF ,F2 ,FCl ,FBr diatomic molecules , Based on the CISD method in the MELD package developed by Davidson and co‐workers ,and com‐bined with our own MF program .We calculate some parameters R（R/a .u .） of molecular face（MF） contour and boundary electron density ED（ED/10^-3 a .u .） of the X and F atoms in these molecules along both vertical and horizontal directions of chemical bonds .When compared the parameters R（R/a .u .） of molecular face contour with its corresponding independent atomic boundary radius ,and re‐lated with the trend of the first ionization energy ,we obtained a conclusion about the fluorine atom side that the smaller the ionization energy is ,the bigger the parameters R（R/a .u .） of molecular face contour ,and the smaller the boundary electron density also .When the nuclear charges of two atoms are same ,the parameters of molecular face contour and boundary electron are symmetrical along the vertical or horizontal direction of chemical bond .The MF studies of the HF ,F2 ,FCl and FBr dia‐tomic molecules provided an effective and reliable method for us to further discuss the nature and characteristics of other diatomic molecules .