Conical Intersections and Nuclear Dynamics: A New Look at an Old Problem

圆锥形交点和核动力学：对老问题的新看法

• 批准号: 0206834
• 负责人: David Yarkony
• 金额: $ 30.6万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-01 至 2005-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0206834&HistoricalAwards=false
• 关键词: Conical; Intersections; Nuclear; Dynamics; New

David Yarkony of Johns Hopkins University is supported by the Theoretical and Computational Chemistry Program to study electronically nonadiabatic processes, in which nuclear motion is not restricted to a single Born-Oppenheimer potential energy surface. The role played by conical intersections in nonadiabatic dynamics is a particular focus. The formal and computational tools to develop a fully adiabatic picture of a spin nonconserving, electronically nonadiabatic process for a system with an odd number of electrons will be developed. These tools will be extended to locate and characterize conical intersections with the spin-orbit interaction included in order to treat the most general situation. For the first time, the locus of this type of conical intersection seam will be determined. The reactions of molecular hydrogen with both ground and excited state OH and SH radicals will be investigated to address the effect of increasing spin-orbit coupling. As well, the predissociation of electronically excited OClO, OBrO, and ultimately OIO will be considered. A clearer picture of the relation between the local topography of a conical intersection and the outcome of the nonadiabatic event is expected to emerge from this research. Understanding molecular potential energy surface crossings is crucially important for describing chemical reactions that involve electronically excited states. The task of describing this topic in quantum chemistry its extremely difficult, and likely to be advanced significantly in this project. Successful outcomes will have a major impact on the characterization of chemical reactions initiated by light absorption.

约翰·霍普金斯大学的 David Yarkony 得到理论和计算化学项目的支持，研究电子非绝热过程，其中核运动不限于单个玻恩-奥本海默势能表面。 圆锥形交叉点在非绝热动力学中所扮演的角色是一个特别关注的焦点。 将开发用于开发具有奇数电子的系统的自旋非守恒、电子非绝热过程的完全绝热图像的形式和计算工具。 这些工具将扩展到定位和表征圆锥形交叉点，并包含自旋轨道相互作用，以处理最一般的情况。 首次确定此类圆锥形相交接缝的轨迹。 将研究分子氢与基态和激发态 OH 和 SH 自由基的反应，以解决增加自旋轨道耦合的影响。 此外，还将考虑电子激发的 OClO、OBrO 和最终 OIO 的预解离。 这项研究预计将更清楚地说明圆锥形交叉点的局部地形与非绝热事件的结果之间的关系。了解分子势能表面交叉对于描述涉及电子激发态的化学反应至关重要。 在量子化学中描述这一主题的任务极其困难，并且可能在该项目中取得显着进展。 成功的结果将对光吸收引发的化学反应的表征产生重大影响。