首页 | 本学科首页   官方微博 | 高级检索  
     检索      

键长-键角和Radau坐标下哈密顿算符在傅里叶基组表象下的厄米性
引用本文:于德权,黄鹤,GunnarNyman,孙志刚.键长-键角和Radau坐标下哈密顿算符在傅里叶基组表象下的厄米性[J].化学物理学报,2016,29(1):112-122.
作者姓名:于德权  黄鹤  GunnarNyman  孙志刚
作者单位:中国科学院大连化学物理研究所分子反应动力学国家重点实验室, 大连 116023,中国科学院大连化学物理研究所分子反应动力学国家重点实验室, 大连 116023;辽宁师范大学物理与电子技术学院, 大连 116029,瑞典哥德堡大学化学学院, 哥德堡,中国科学院大连化学物理研究所分子反应动力学国家重点实验室, 大连 116023;中国科学与技术大学, 量子信息与量子科技前沿协同创新中心, 合肥 230026
摘    要:在量子动力学计算中,有时候为了规避奇点问题或者节省计算量,我们经常需要对哈密顿量进行变换. 然而,在使用傅里叶基矢计算时,哈密顿量的变换形式容易导致哈密顿矩阵失去厄米性,进而有些情况下使数值计算变得不稳定. 本文主要讨论构建具有厄米性的哈密顿算符的方法. 以三原子分子为例,构建了键长—键角和Radau坐标下描述分子运动的各种形式的哈密顿量. 基于这些哈密顿量,采用含时波包方法计算了OClO分子的吸收光谱,讨论了非厄米性矩阵对计算结果的影响. 本文所得到的结论对基于基函数展开的量子动力学计算都是适用的.

关 键 词:哈密顿量  快速傅里叶变换  傅里叶基组  含时波包方法  吸收光谱
收稿时间:7/4/2015 12:00:00 AM
修稿时间:2015/7/13 0:00:00

Hermiticity of Hamiltonian Matrix using the Fourier Basis Sets in Bond-Bond-Angle and Radau Coordinates
De-quan Yu,He Huang,Gunnar Nyman and Zhi-gang Sun.Hermiticity of Hamiltonian Matrix using the Fourier Basis Sets in Bond-Bond-Angle and Radau Coordinates[J].Chinese Journal of Chemical Physics,2016,29(1):112-122.
Authors:De-quan Yu  He Huang  Gunnar Nyman and Zhi-gang Sun
Institution:State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computa-tional Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Science, Dalian 116023, China,State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computa-tional Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Science, Dalian 116023, China;School of Physics and Electronic Technology, Liaoning Normal University, Dalian 116029, China,Department of Chemistry, Physical Chemistry, Göteborg University, SE-412 96 Göteborg, Sweden and State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical and Computa-tional Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Science, Dalian 116023, China;Center for Advanced Chemical Physics and 2011 Frontier Center for Quantum Science and Technol-ogy, University of Science and Technology of China, Hefei 230026, China
Abstract:In quantum calculations a transformed Hamiltonian is often used to avoid singularities in a certain basis set or to reduce computation time. We demonstrate for the Fourier basis set that the Hamiltonian can not be arbitrarily transformed. Otherwise, the Hamiltonian matrix becomes non-hermitian, which may lead to numerical problems. Methods for correctly constructing the Hamiltonian operators are discussed. Specific examples involving the Fourier basis functions for a triatomic molecular Hamiltonian (J=0) in bond-bond angle and Radau coordinates are presented. For illustration, absorption spectra are calculated for the OClO molecule using the time-dependent wavepacket method. Numerical results indicate that the non-hermiticity of the Hamiltonian matrix may also result from integration errors. The conclusion drawn here is generally useful for quantum calculation using basis expansion method using quadrature scheme.
Keywords:Discrete variable representation  Hermiticity  Time-dependent wavepacket method  Absorption spectra
点击此处可从《化学物理学报》浏览原始摘要信息
点击此处可从《化学物理学报》下载免费的PDF全文
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号