...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The journal of physical chemistry, A. Molecules, spectroscopy, kinetics, environment, & general theory >Analytic Gradients for the Spin-Flip ORMAS-CI Method: Optimizing Minima, Saddle Points, and Conical Intersections
【24h】

Analytic Gradients for the Spin-Flip ORMAS-CI Method: Optimizing Minima, Saddle Points, and Conical Intersections

机译：旋转翻转ormas-CI方法的分析梯度：优化MIMIMA，马鞍点和锥形交叉口

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

Analytic nuclear gradients are derived and implemented for the recently introduced SF-ORMAS-CI (spin-flip occupation restricted multiple active space CI) method. Like most SF methods, SF-ORMAS-CI successfully describes bond breaking, diradical systems, transition states, and low-lying excited states, without suffering from spin contamination. The availability of analytic gradients now enables the efficient optimization of equilibrium structures in both ground and excited electronic states, as well as the computation of seminumerical Hessians. Therefore, it is now possible to determine minima, transition states, and conical intersections using the SF-ORMAS-CI method without the need for numerical differentiation. In the present study the SF-ORMAS method and gradient are applied to optimize structures for several organic molecules, such as ethylene, azomethane, and trimethylmethylene. In most cases, structures optimized with SF-ORMAS are almost identical to those obtained using other multireference methods, despite the lack of dynamic correlation in SF-ORMAS.
机译：分析核梯度是为最近引入的SF-ORMA-CI（自旋翻转占用限制多功能空间CI）方法而实施的分析核梯度。与大多数SF方法一样，SF-ORMAS-CI成功地描述了债券破碎，Diradical Systems，过渡状态和低洼兴奋状态，而不会遭受旋转污染。分析梯度的可用性现在能够在地面和激励的电子状态下有效地优化均衡结构，以及多个霍森斯的计算。因此，现在可以使用SF-ORMAS-CI方法确定最小值，转换状态和锥形交叉点，而无需数值分化。在本研究中，SF-ormas方法和梯度用于优化几种有机分子的结构，例如乙烯，氮杂甲烷和三甲基亚甲基。在大多数情况下，尽管SF-ORMAS中缺乏动态相关性，但是用SF-ormas优化的结构几乎与使用其他多引用方法获得的结构。

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