乙炔分子的低能电子弹性散射研究

Low energy electron scattering with acetylene molecule

本文采用R矩阵方法研究低能电子与乙炔分子的弹性散射截面及其动力学过程.研究采用静态交换势模型(SE)和静态交换加极化势模型(SEP)两种方法.结果显示当前SEP模型预测的弹性散射截面与已有的实验值和理论结果符合的很好.SE模型预测了一个位于4.75 eV,宽度为3.0 eV的π形状共振态.该共振态在SEP模型中的位置降低为2.65 eV,宽度为1.5 eV.它来自B_(2g)和B_(3g)对称性贡献,理论预测共振态位置与实验值符合的很好.我们讨论了考虑不同的虚轨道对共振态的影响,说明预测精确的共振态的位置需要准确的处理极化效应.基于SEP模型得到的K矩阵元,我们使用POLYDCS代码计算的散射微分截面(DCS),和实验值符合的较好.除此之外,我们还报道了2 eV时转动分辨的态-态微分截面.

In this paper R-matrix method is used to study the elastic scattering cross section and the dynamic process of the low-energy electron scattering with the acetylene molecule.The static exchange model(SE)and the static exchange plus polarization model(SEP)were used.The results show that the elastic scattering cross section predicted by the current SEP model is in good agreement with the experimental and theoretical results.The SE model predicts aπ-shaped resonant state at 4.75 eV with a width of 3.0 eV.The position of the resonant state decreases to 2.65 eV in the SEP model and 1.5 eV in width.The resonance is derived from the symmetry of B 2g and B 3g.The theoretical predicted resonant position agrees well with the experimental data.In addition,we get the differential scattering cross sections(DCSs)calculated by K-matrix element based on R-matrix.The results are in good agreement with the existing theoretical results.