• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Chemistry: A European journal >An Evaluation of Force-Field Greatments of Aromatic Interactions
【24h】

An Evaluation of Force-Field Greatments of Aromatic Interactions

机译：芳香相互作用力场的评价

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

Experimental measurements of edge-to-face aromatic interactions have been used to test a series of molecular mechanics force fields. The experimental data were determined for a range of differently substituted aromatic rings using chemical double mutant dycles on hydrogen-bonded zipper complexes. These complexes were truncated for the purposes of the molecular mechanics calculations so that problems of conformational searching and the optimisation of large structures could be avoided. Double-mutant cycles were then carried out in silico using these truncated systems. Comparison of the experimental aromatic interaction energies and the X-ray crystal structures of these truncated complexes with the calculated data show that conventional molecular mechanics force fields (MM2, MM3, AMBER and OPLS) do not peroform well. However, the XED force field which explicitly represents electron nisotropy as an expansion of point charges around each atom reproduces the trends in interaction energy and the three-dimensional structures exceedingly well. Collapsing the XED charges onto atom centres or the use of semi-empirical atom-centred charges within the XED force field gives poor results. Thus the success fo XED is not related to the methods used to assign the atomic charge distribution but can be directly attributed to the use of off-atom centre charges.
机译：边对面芳族相互作用的实验测量已用于测试一系列分子力学力场。使用氢键结合的拉链上的化学双突变体，确定了一系列不同取代的芳环的实验数据。为了分子力学计算的目的，这些络合物被截短，从而可以避免构象搜索和大型结构优化的问题。然后使用这些截短的系统在计算机上进行双突变周期。这些截短的配合物的实验芳香族相互作用能和X射线晶体结构与计算数据的比较表明，传统的分子力学力场（MM2，MM3，AMBER和OPLS）表现得不好。但是，XED力场明确表示电子各向异性，即每个原子周围点电荷的扩展，很好地再现了相互作用能和三维结构的趋势。将XED电荷折叠到原子中心上，或者在XED力场内使用半经验原子为中心的电荷会产生较差的结果。因此，XED的成功与用于分配原子电荷分布的方法无关，而可以直接归因于原子外中心电荷的使用。

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