• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>RSC Advances >Local electric field factors by a combined charge-transfer and point-dipole interaction model
【24h】

Local electric field factors by a combined charge-transfer and point-dipole interaction model

机译：局部电场因子通过组合电荷 - 转移和点偶极交互模型

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

A force-field model for the local electric field as a linear response to a frequency-dependent external electric field is presented based on a combined charge-transfer and point-dipole interaction (CT-PDI) force-field model for frequencies through the first absorption maximum. The local electric field provides a measure of the mutual interactions of the molecules with each other, as is important in problems ranging from dielectric breakdown to solvent polarization and energy transfer. It also indicates how resonant excitation of these molecules can perturb Raman scattering by a third molecule located nearby through an intensity borrowing mechanism. The CT-PDI model is a combination of a modified electronegativity equalization model including non-metallic behaviour and a point-dipole interaction model described by atomic polarizabilities which also includes the time-dependence of the atomic charges and atomic dipole moments. A parametrization of frequency-dependent polarizabilities through the first absorption maximum calculated by time-dependent density-functional theory has been extended for a set of hydrocarbon and azobenzene molecules to provide atom-type parameters for the CT-PDI model. As initial model systems, results are presented for the benzene and azobenzene dimers for the local electric field response at points between the molecules and at the atoms in the molecules. As expected, the response depends critically on the intermolecular distance between the monomers. The azobenzene dimer shows a larger local field response at the atoms in the phenyl rings compared to the benzene dimer and the response at the nitrogen atoms is larger than at the hydrogen and carbon atoms in the azobenzene dimer, which can be rationalized qualitatively by the charge and dipole contributions to the local field factor either adding up or to a large extent cancelling each other. At the absorption frequency, the largest local field factor of the benzene dimer is around 6 and for the azobenzene dimer it is around 12, respectively, at typical distances, indicating that the response may be significant.
机译：对于局部电场，以一个频率相关的外部电场的线性响应的力场模型提出了一种基于组合电荷转移和点 - 偶极相互作用（CT-PDI）力场通过第一模型的频率最大吸收。局部电场提供彼此分子的相互作用的量度，如在问题，从介质击穿到溶剂极化和能量转移重要。它还指示如何对这些分子的共振激发可以通过位于附近通过的强度借贷机构的第三分子扰乱拉曼散射。的CT-PDI模型是经修饰的电负性均衡模型包括非金属行为和通过原子极化其中还包括的原子电荷和原子偶极矩的时间依赖性描述的点 - 偶极相互作用模型的组合。通过时间依赖密度泛函理论计算的第一最大吸收频率相关的极化率的参数化已扩展的一组烃和偶氮苯分子为​​CT-PDI模型提供原子型参数。如初始模型系统中，结果被呈现为苯和偶氮苯的二聚体在分子之间和在分子中的原子数的点的局部电场的响应。正如预期的那样，响应关键取决于单体之间的分子间距离。偶氮苯二聚体示出了在苯环的原子比苯二聚物，并在氮原子上的反应更大的局部场响应比在偶氮苯二聚体的氢和碳原子，其可以定性地由电荷合理化较大和本地字段因子偶极贡献或者相加或者在很大程度上相互抵消。在吸收频率，苯二聚体的最大局部场因子约为6和偶氮苯的二聚体，其为大约12，分别在典型距离，表明该响应可以是显著。

著录项

  • 来源
    《RSC Advances》 |2015年第40期|共12页
  • 作者

    Davari Nazanin; Haghdani Shokouh; Astrand Per-Olof; Schatz George C.;

  • 作者单位

    Norwegian Univ Sci &

    Technol NTNU Dept Chem NO-7491 Trondheim Norway;

    Norwegian Univ Sci &

    Technol NTNU Dept Chem NO-7491 Trondheim Norway;

    Norwegian Univ Sci &

    Technol NTNU Dept Chem NO-7491 Trondheim Norway;

    Northwestern Univ Dept Chem Evanston IL 60208 USA;

  • 收录信息
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 化学;
  • 关键词

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