Additivity Rule for Electron-Molecule Total Cross Section Calculations at 50-5000 eV： A Geometrical Approach  

作　　者：施德恒 孙金锋 马恒 朱遵略 杨向东 

机构地区：[1]College of Physics and Information Engineering, Henan Normal University, Xinxiang 453007 [2]Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065

出　　处：《Chinese Physics Letters》2007年第10期2819-2822,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China under Grand No 10574039.

摘　　要：To quantify the changes of the geometric shielding effect in a molecule as the incident electron energy varies, we present an empirical fraction, which represents the total cross section （TCS） contributions of shielded atoms in a molecule at different energies. Using this empirical fraction, a new formulation of the additivity rule is proposed. Using this new additivity rule, the TCSs for electron scattering by CO2, C2H2, C6H12 （cyclo-hexane） and CsH16 （cyclo-octane） are calculated in the range 50-5000 e V. Here the atomic cross sections are derived from the experimental TCS results of simple molecules （H2, O2, CO）. The quantitative TCSs are compared with those obtained by experiments and other theories, and good agreement is attained over a wide energy range.To quantify the changes of the geometric shielding effect in a molecule as the incident electron energy varies, we present an empirical fraction, which represents the total cross section （TCS） contributions of shielded atoms in a molecule at different energies. Using this empirical fraction, a new formulation of the additivity rule is proposed. Using this new additivity rule, the TCSs for electron scattering by CO2, C2H2, C6H12 （cyclo-hexane） and CsH16 （cyclo-octane） are calculated in the range 50-5000 e V. Here the atomic cross sections are derived from the experimental TCS results of simple molecules （H2, O2, CO）. The quantitative TCSs are compared with those obtained by experiments and other theories, and good agreement is attained over a wide energy range.

关 键 词：POLYATOMIC-MOLECULES SCATTERING IMPACT C2H2 CO ENERGIES ATOMS HCN 

分 类 号：O46[理学—电子物理学]