一种计算中、高能电子被分子散射总截面的修正势方法

A modification potential method for total cross section calculation of electron scattering by molecules at medium and high energies

在考虑分子内成键原子间的电子云重叠效应的基础上,提出了一种能够在中、高能区准确计算“电子_分子”散射总截面的修正势方法.利用可加性规则及Hartree_Fock波函数,使用这一修正过的复光学势,在30—5000eV内对电子被4个等电子(Z=18)分子(HCl,H2S,PH3和SiH4)散射的总截面进行了计算,并将理论计算值与实验结果及其他理论值进行了比较.结果表明,利用这一修正过的复光学势及可加性规则进行计算,所得理论值与实验结果更为接近.因此在复光学势中采用本文提出的这一修正方法,可提高中、高能电子被分子散射的总截面的计算准确性.

Taking into consideration the overlapping effect of electron clouds between two atoms in a molecule, a modification method is presented which can be used to calculate the total cross sections for electron scattering from numerous molecules at medium and high energies. The modified complex optical potential composed of static, exchange, polarization plus absorption is directly employed to calculate the total cross sections for electron scattering from isoelectronic molecules （HCl, H2 S, PH3 and SiH4 ） over the energy range 30--5000 eV using the additivity rule model at Hartree-Fock level. The obtained quantitative molecular total cross sections are compared with those obtained by experiments and other theories wherever available, and good agreement is obtained. It is shown that the additivity rule model together with the modified complex optical potential can give much better results than the unmodified one. So, the modification potential method presented here can improve the accuracy of the total cross section calculations of electron scattering from molecules.