• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The Journal of Chemical Physics >Isotopic equilibria in aqueous clusters at low temperatures: Insights from the MB-pol many-body potential
【24h】

Isotopic equilibria in aqueous clusters at low temperatures: Insights from the MB-pol many-body potential

机译：在低温下的水簇中的同位素均衡：来自MB-POL许多身体潜力的见解

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

By combining path-integrals molecular dynamics simulations with the accurate MB-pol potential energy surface, we investigate the role of alternative potential models on isotopic fractionation ratios between H and D atoms at dangling positions in water clusters at low temperatures. Our results show clear stabilizations of the lighter isotope at dangling sites, characterized by free energy differences Delta G that become comparable to or larger than k(B)T for temperatures below similar to 75 K. The comparison between these results to those previously reported using the empirical q-TIP4P/F water model [P. E. Videla et al., J. Phys. Chem. Lett. 5, 2375 (2014)] reveals that the latter Hamiltonian overestimates the H stabilization by similar to 25%. Moreover, predictions from the MB-pol model are in much better agreement with measured results reported for similar isotope equilibria at ice surfaces. The dissection of the quantum kinetic energies into orthogonal directions shows that the dominant differences between the two models are to be found in the anharmonic characteristics of the potential energy surfaces along OH bond directions involved in hydrogen bonds. Published by AIP Publishing.
机译：通过将路径积分的分子动力学模拟与精确的MB-POL电位相结合，我们研究了替代潜在模型对低温下水簇中的悬空位置的同位素分馏比对同位素分馏比的作用。我们的结果表明，在悬空部位的摇摆位点的较轻同位素的清晰稳定性，其特征在于与低于75k的温度的温度或大于K（b）t的可比能量差异Δg。这些结果与先前报告的那些结果之间的比较经验Q-Tip4p / f水模型[P. E.Videla等人。，J. Phy。化学。吧。 5,2375（2014）]揭示后者哈密顿人民高估了H稳定化，类似于25％。此外，从MB-POL模型预测与报告在冰面类似的同位素平衡测试结果更好的协议。量子动力学进入正交方向的解剖表明，两种模型之间的主导差异将在沿氢键中涉及的OH键合方向的潜在能量表面的Anharmonic特性中找到。通过AIP发布发布。

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