• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Chemistry: A European journal >The HgF2 Ionic Switch: A Triumph of Electrostatics against Relativistic Odds
【24h】

The HgF2 Ionic Switch: A Triumph of Electrostatics against Relativistic Odds

机译：HgF2离子开关：相对于相对论可能性的静电的胜利

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 remarkable transition in the chemical bonding in (HgF2)(n) clusters as a function of n is identified and characterized. HgF2 is a fascinating material. Certain significant consequences of relativistic effects on the structure of the HgF2 molecule, dimer, and trimer disappear in the extended solid. Relativistic effects in Hg ensure that HgX2 molecules (X F, Cl, Br, and I) are linear, rigid, and form weakly bound dimers and trimers held together by weak electrostatic and van der Waals-type forces (unlike ZnX2 and CdX2 systems in which the intermonomer contacts are strong polar covalent bonds). For HgF2, the location and nature of an apparent transition from weak interactions in the smallest (HgF2) n clusters to ionic bonding in the (fluorite) HgF2 extended solid has remained a mystery. Computational evidence obtained at the M06-2X, B97D3, and MP2 levels of theory and reported herein indicate that polar covalent bonding in (HgF2)(n) begins as early as n=5. For n=2 through to n=13, the transition or switch from weak (primarily dipole-dipole-type) intermonomer interactions to a preference for polar covalent bonding occurs within the range 5 < n <= 9. Thermodynamic evidence for this transition is provided. Our results demonstrate a significant risk associated with crystal structure prediction from the ground up (i.e., based on bonding patterns in small clusters). The path from monomers through to extended solids may be punctuated at one or several points (as n increases) with transitions in structure and bonding that are not anticipated or betrayed by the bonding in small clusters.
机译：确定并表征了（HgF2）（n）团簇中化学键与n的显着过渡。 HgF2是一种令人着迷的材料。相对论效应对HgF2分子，二聚体和三聚体结构的某些重大影响在扩展的固体中消失了。汞中的相对论效应确保HgX2分子（XF，Cl，Br和I）是线性的，刚性的，并形成弱结合的二聚体和三聚体，它们通过弱的静电力和范德华型力保持在一起（不同于ZnX2和CdX2系统，其中单体间的接触是强极性共价键）。对于HgF2，从最小的（HgF2）n簇中的弱相互作用到（萤石）HgF2扩展固体中的离子键的明显过渡的位置和性质仍然是个谜。在M06-2X，B97D3和MP2的理论水平上获得的计算证据，并在本文中进行了报道，表明（HgF2）（n）中的极性共价键最早在n = 5时开始。对于n = 2到n = 13，在5

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