首页> 外文期刊>The Journal of Chemical Physics >Hydration properties of magnesium and calcium ions from constrained first principles molecular dynamics
【24h】

Hydration properties of magnesium and calcium ions from constrained first principles molecular dynamics

机译:受约束的第一原理分子动力学对镁和钙离子的水化性质

获取原文
获取原文并翻译 | 示例
           

摘要

We studied the solvation structures of the divalent metal cations Mg2+ and Ca2+ in ambient water by applying a Car-Parrinello-based constrained molecular dynamics method. By employing the metal-water oxygen coordination number as a reaction coordinate, we could identify distinct aqua complexes characterized by structural variations of the first coordination shell. In particular, our estimated free-energy profile clearly shows that the global minimum for Mg2+ is represented by a rather stable sixfold coordination in the octahedral arrangement, in agreement with experiments. Conversely, for Ca2+ the free-energy curve shows several shallow local minima, suggesting that the hydration structure of Ca2+ is highly variable. Implications for water exchange reactions are also discussed. (c) 2007 American Institute of Physics.
机译:我们应用基于Car-Parrinello的约束分子动力学方法研究了环境水中二价金属阳离子Mg2 +和Ca2 +的溶剂化结构。通过将金属-水的氧配位数用作反应坐标,我们可以鉴定出以第一配位壳的结构变化为特征的独特的水配合物。特别是,我们估算的自由能曲线清楚地表明,与实验相一致,Mg2 +的全球最低限度由八面体排列中相当稳定的六重配位表示。相反,对于Ca2 +,自由能曲线显示出几个浅的局部最小值,这表明Ca2 +的水合结构是高度可变的。还讨论了水交换反应的含义。 (c)2007年美国物理研究所。

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