Barbosa Alessandra Souza, Bettega Márcio H F
Departamento de Física, Universidade Federal do Paraná, Caixa Postal 19044, 81531-990 Curitiba, Paraná, Brazil.
J Chem Phys. 2014 Dec 28;141(24):244307. doi: 10.1063/1.4904704.
We report calculated cross sections for elastic scattering of low-energy electrons by cyclohexane (c-C6H12). We employed the Schwinger multichannel method implemented with norm-conserving pseudopotentials in the static-exchange and static-exchange plus polarization approximations, for impact energies up to 30 eV. We compare our calculated integral cross section with experimental total cross sections available in the literature. We also compare our calculated differential cross sections (DCSs) with experimental results for benzene and experimental and theoretical results for 1,4-dioxane, in order to investigate the similarities between those molecules under electron collisions. Although benzene is a cyclic six-carbon molecule, as cyclohexane, we found that the differential cross sections of the latter are more similar to those of 1,4-dioxane than those of benzene. These similarities suggest that the geometry may play an important role in the behavior of the DCSs of these molecules. Our integral cross section displays a broad structure at around 8.5 eV, in agreement with the total cross section experimental data of 8 eV and vibrational excitation data of 7.5 eV. The present integral cross section also shows the presence of a Ramsauer-Townsend minimum at around 0.12 eV. In general, our integral cross section shows a qualitative agreement with the experimental total cross section.
我们报告了环己烷（c-C6H12）对低能电子弹性散射的计算截面。我们采用了施温格多通道方法，在静态交换和静态交换加极化近似下，使用守恒规范赝势，计算了高达30 eV的碰撞能量下的截面。我们将计算得到的积分截面与文献中可用的实验总截面进行了比较。我们还将计算得到的微分截面（DCS）与苯的实验结果以及1,4 - 二氧六环的实验和理论结果进行了比较，以研究这些分子在电子碰撞下的相似性。尽管苯是一个环状六碳分子，与环己烷类似，但我们发现环己烷的微分截面与1,4 - 二氧六环的微分截面比与苯的微分截面更相似。这些相似性表明，几何结构可能在这些分子的微分截面行为中起重要作用。我们的积分截面在约8.5 eV处呈现出一个宽结构，这与8 eV的总截面实验数据和7.5 eV的振动激发数据一致。目前的积分截面在约0.12 eV处还显示出一个拉姆绍尔 - 汤森极小值。总体而言，我们的积分截面与实验总截面在定性上是一致的。
