• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The journal of physical chemistry, A. Molecules, spectroscopy, kinetics, environment, & general theory >Collision-Energy-Resolved Penning Ionization Electron Spectroscopy of Glycine with He(2~3S) Metastable Atoms: Conformational Isomers in Collisional Ionization
【24h】

Collision-Energy-Resolved Penning Ionization Electron Spectroscopy of Glycine with He(2~3S) Metastable Atoms: Conformational Isomers in Collisional Ionization

机译：甘氨酸与He（2〜3S）亚稳原子的碰撞能量分辨潘宁电离电子能谱：碰撞电离中的构象异构体

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Conformationally dependent ionization of the simplest amino acid, glycine, is studied by Penning ionizationelectron spectroscopy with velocity-resolved metastable He*(23S) atoms. The observed He I ultravioletphotoelectron and Penning ionization electron spectra are reproduced by superimposed theoretical spectra,assuming thermal distributions of conformers. The conformations of amino acids are determined by analyzingthe observed Penning ionization cross sections, peak shifts, and collision energy dependences of partialionization cross sections (CEDPICS). The Penning ionization cross sections are governed by collisionallyaccessible exterior electron densities. When the amino and carbonyl groups are exposed to He* access, thenonbonding orbitals of N (nN) and 0 atoms (no) give rise to strong bands. The observed negative peak shiftsand negative CEDPICS for the nr, and no orbitals suggest the presence of attractive interactions around theirelectron distributions. The most attractive wells are estimated to be ～400 meV in the direction of the nNorbitals by ab initio model calculations. A conformer possessing dual hydrogen bonds contributes predominantlyto the spectra.
机译：最简单的氨基酸甘氨酸的构象依赖性电离是通过潘宁电离电子能谱和速度分辨的亚稳态He *（23S）原子进行研究的。假定构象异构体的热分布，通过叠加理论光谱，可以再现观察到的He I紫外光电子光谱和Penning电离电子光谱。氨基酸的构象是通过分析观察到的Penning电离截面，峰位移和部分电离截面的碰撞能量依赖性（CEDPICS）来确定的。潘宁电离截面受碰撞可访问的外部电子密度控制。当氨基和羰基暴露于He *通道时，N（nN）和0原子（no）的非键合轨道会产生强能带。对于nr观察到负峰位移和CEDPICS为负，并且没有轨道表明在其电子分布周围存在吸引作用。通过从头算模型计算，在n轨道方向上，最吸引人的井估计为〜400 meV。具有双氢键的构象异构体主要对光谱有贡献。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号