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A multi-dimensional microcanonical Monte Carlo study of S_0→T_1 intersystem crossing of isocyanic acid
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作者 ZHANG Feng1,2,FANG WeiHai1,LUO Yi2 & LIU RuoZhuang1 1 College of Chemistry,Beijing Normal University,Beijing 100875,China 2 Theoretical Chemistry,School of Biotechnology,Royal Institute of Technology,S-10691 Stockholm,Sweden 《Science China Chemistry》 SCIE EI CAS 2009年第11期1885-1891,共7页
A general formula for the multi-dimensional Monte Carlo microcanonical nonadiabatic rate constant expressed in configuration space is applied to calculate the rate of intersystem crossing(ISC) between the ground(S0) a... A general formula for the multi-dimensional Monte Carlo microcanonical nonadiabatic rate constant expressed in configuration space is applied to calculate the rate of intersystem crossing(ISC) between the ground(S0) and first excited triplet(T1) states for isocyanic acid.One-,two-and three-dimensional potential energy surfaces are constructed by coupled-cluster single-double CCSD calculations,which are used for Monte Carlo sampling.The calculated S0→T1 ISC rate is in good agreement with experimental findings,which gives us a reason to believe that the multi-dimensional Monte Carlo microcanonical nonadiabatic rate theory is a very effective method for calculating nonadiabatic transition rate of a polyatomic molecule. 展开更多
关键词 MULTI-DIMENSIONAL MONTE Carlo MICROCANONICAL nonadiabatic rate theory intersystem CROSSING isocyanic ACID nonadiabatic transition
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马约拉纳零能模移动引起的非绝热跃迁和粒子数宇称破坏及其检测
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作者 王琼瑶 白婧 +2 位作者 徐露婷 冯伟 李新奇 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第4期476-481,共6页
拓扑超导体中马约拉纳零能模(MZMs)的移动,对拓扑量子计算具有重要作用.基于微观格点模型,本文模拟了微电极操控下的多段移动及移动过程中引起的非绝热跃迁.结果表明多段移动可降低非绝热跃迁概率.经过准粒子激发谱的非绝热跃迁,还将诱... 拓扑超导体中马约拉纳零能模(MZMs)的移动,对拓扑量子计算具有重要作用.基于微观格点模型,本文模拟了微电极操控下的多段移动及移动过程中引起的非绝热跃迁.结果表明多段移动可降低非绝热跃迁概率.经过准粒子激发谱的非绝热跃迁,还将诱导一对MZMs的初始费米宇称的微弱破坏(二阶效应).本文提出的检测非绝热跃迁效应的方案,可以同时检测因移动MZMs引起的跃迁至激发态的概率,以及因二阶效应引起的初始费米宇称的破坏. 展开更多
关键词 拓扑超导量子线 马约拉纳零能模 非绝热跃迁
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金属氢化物中质子耦合电子转移反应的理论研究
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作者 刘晓云 但晓寒 史强 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第2期199-210,I0102,共13页
金属-氢配合物在多种催化反应中起着重要作用最近的研究表明,与吡啶基团共价连接的钨氢配合物可以发生协同的质子耦合电子转移反应.本文使用密度泛函理论和非绝热速率理论研究了该类弱氢键体系中的协同质子耦合电子转移反应.首先通过密... 金属-氢配合物在多种催化反应中起着重要作用最近的研究表明,与吡啶基团共价连接的钨氢配合物可以发生协同的质子耦合电子转移反应.本文使用密度泛函理论和非绝热速率理论研究了该类弱氢键体系中的协同质子耦合电子转移反应.首先通过密度泛函理论构建了金属-氢配合物质子自由度的二维势能面.然后求解薛定方程得到了波函数和振动能级,并用于分析各对振动态之间的跃迁速率和总的速率常数.结果表明,由于质子给体-受体之间距离的热涨落,即使在质子给体和受体之间仅存在弱氢键的情况下,协同质子耦合电子转移反应和总反应速率常数也可以得到显著增强. 展开更多
关键词 质子耦合电子转移 速率常数 密度泛函理论计算 非绝热 跃迁
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Field-dependent rate constant for intramolecular electron transfer reactions
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作者 李象远 田安民 +1 位作者 何福城 鄢国森 《Chinese Science Bulletin》 SCIE EI CAS 1995年第20期1698-1702,共5页
Electron transfer (ET) reactions are of great importance to nearly every subdiscipline of chemistry. Marcus classical model, quantum model treating the nuclei as a quantum system, and the semiclassical model neglectin... Electron transfer (ET) reactions are of great importance to nearly every subdiscipline of chemistry. Marcus classical model, quantum model treating the nuclei as a quantum system, and the semiclassical model neglecting the nuclear tunneling effects but taking the nonadiabatic transition between two electronic states into account, have been widely used in the kinetic research of ET reactions. For the symmetric double-well potential vs. the nuclear configuration Q along the reaction path (fig.1(a)), a semiclassical kinetic model 展开更多
关键词 EXTERNAL electric FIELD electron transfer nonadiabatic transition transition state rate constant.
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Coupling matrix element of electron self-exchange reactions in solution
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作者 步宇翔 刘成卜 邓从豪 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1998年第6期509-513,共5页
On the basis of the common feature among the electron transfer process and the ion hydration process as well as the relevant experimental kinetic data of electron trader reaction, a new accurate hydration potential fu... On the basis of the common feature among the electron transfer process and the ion hydration process as well as the relevant experimental kinetic data of electron trader reaction, a new accurate hydration potential function scheme for the determination of electron transfer coupling matrix element is presented. The coupling matrix element between two hydrated ions of the reacting system in solution is calculated. The results and the applicability of this scheme are discussed. 展开更多
关键词 Electron transfer reaction coupling matrix element nonadiabatic transition hydration potential function
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Theoretical Study on the Long-lived Complexes for the Na +I_2Collision System
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作者 XiaoMinSUN DaChengFENG ZhengTingCAI 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第6期749-752,共4页
For the Na + I2 collision system, theoretical study is performed on the QCISD(T) level by using ab initio method. The ab initio potential energy surfaces are got and on them the long-lived complexes are found and opti... For the Na + I2 collision system, theoretical study is performed on the QCISD(T) level by using ab initio method. The ab initio potential energy surfaces are got and on them the long-lived complexes are found and optimized. These results verify the crossed molecule beam experimental phenomenon and the detailed geometry structures are given for the first time. The role of the complexes in the reaction path is also described in detail. 展开更多
关键词 nonadiabatic transition ion-pair formation two-state potential energy surface long-lived complex.
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Theoretical Study on the Ion-pair Formation Mechanism for the Li+I_2 →Li^+ + I_2^- System
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作者 SUNXiao-Min FENGDa-Cheng CAIZheng-Ting 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第5期498-501,共4页
For the Li + I2 →Li+ + I2- system, theoretical study has been performed on the QCISD(T) level by using the ab initio method. The collision complex in ion-pair formation process was found and optimized. These results ... For the Li + I2 →Li+ + I2- system, theoretical study has been performed on the QCISD(T) level by using the ab initio method. The collision complex in ion-pair formation process was found and optimized. These results show that the crossed molecule beam (CMB) experimental phenomenon is verified and the detailed geometry is given for the first time. A mechanism for ion-pair formation was proposed in detail. The position where the collision complex occurs affects the reaction path. Specifically, the process has threshold when the collision complex appeared before the crossing point between the covalent and ionic state potential energy surfaces. On the contrary, the process has no threshold after the crossing point. Theoretically, the title system belongs to the former case. 展开更多
关键词 nonadiabatic transition two-state potential energy surface ion-pair formation
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非线性两能级系统中的Landau-Zener-Coulomb跃迁
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作者 豆福全 胡丹 孙建安 《原子与分子物理学报》 CAS 北大核心 2022年第3期16-21,共6页
非线性跃迁动力学的研究是量子操控中的一个重要课题,在原子分子光物理、量子信息以及固体物理等领域都有着重要的应用.本文研究了具有粒子间相互作用两能级系统中的Landau-Zener-Coulomb跃迁动力学.结果表明,对于能级的斜率正负不同的... 非线性跃迁动力学的研究是量子操控中的一个重要课题,在原子分子光物理、量子信息以及固体物理等领域都有着重要的应用.本文研究了具有粒子间相互作用两能级系统中的Landau-Zener-Coulomb跃迁动力学.结果表明,对于能级的斜率正负不同的情况,粒子间相互作用对系统跃迁动力学的影响完全不同.为正时,粒子间相互作用总是抑制能级间的非绝热跃迁,且相互作用强度越大,两能级间的非绝热跃迁越难发生.而为负时,弱相互作用会促进能级间的非绝热跃迁,在强相互作用情况下,跃迁概率会出现振荡.随着相互作用强度的增大,振荡幅度逐渐减小,能级间的非绝热跃迁受到抑制. 展开更多
关键词 Landau-Zener-Coulomb模型 粒子间相互作用 非绝热跃迁
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[2+4]光环加成中的非绝热相互作用
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作者 李象远 何福城 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 1992年第6期834-836,共3页
The S1→S0 nonadiabatic coupling terms are calculated for different reaction modes of concerted [2 + 4] photocycloadditions in the Huckel-Hubbard approximation. The nonadiabatic transition probabilities are estimated ... The S1→S0 nonadiabatic coupling terms are calculated for different reaction modes of concerted [2 + 4] photocycloadditions in the Huckel-Hubbard approximation. The nonadiabatic transition probabilities are estimated by means of the Landau-Zener model as well. The calculated nonadiabatic coupling terms and transition probabilities show clearly the differences between the nonadiabatic interactions of the two reaction modes s+a (or a+s) and s+s. With these calculated results the stereospecifities in concerted [2+4] photocycloadditions are correctly predicted. 展开更多
关键词 光环加成 非绝热偶合 跃迁几率
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多维微正则蒙特卡罗方法计算异氰酸S_0→T_1系间窜跃速率
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作者 张凤 方维海 +1 位作者 罗毅 刘若庄 《中国科学(B辑)》 CSCD 北大核心 2009年第11期1430-1436,共7页
推导了通用的坐标空间多维蒙特卡罗微正则非绝热速率计算公式,并应用于计算异氰酸基态(S0)到第一激发三态(T1)的系间窜跃(ISC)速率.在CCSD水平上构建了一,二,三维势能面用于蒙特卡罗抽样.计算所得S0→T1ISC速率与实验符合较好,因此可以... 推导了通用的坐标空间多维蒙特卡罗微正则非绝热速率计算公式,并应用于计算异氰酸基态(S0)到第一激发三态(T1)的系间窜跃(ISC)速率.在CCSD水平上构建了一,二,三维势能面用于蒙特卡罗抽样.计算所得S0→T1ISC速率与实验符合较好,因此可以预期多维蒙特卡罗微正则非绝热速率理论将成为计算多原子分子非绝热反应速率的有效手段之一. 展开更多
关键词 多维蒙特卡罗微正则非绝 热速率理论 系间窜跃 异氰酸 非绝热跃迁
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Hückel-Hubbard参数化法及氮叶立德[2,3]和氢[1,3]σ键迁移的研究
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作者 何福城 李象远 《高等学校化学学报》 CSCD 北大核心 1994年第7期1030-1033,共4页
本文建议一种Hückel-Hubbard参数化法,并用Hückel-Hubbard理论首次计算了氮叶立德[2,3]和氢[1,3]σ键迁移反应的基态和低激发态势能面,根据计算得到的势能面,对相应的基态和激发态反... 本文建议一种Hückel-Hubbard参数化法,并用Hückel-Hubbard理论首次计算了氮叶立德[2,3]和氢[1,3]σ键迁移反应的基态和低激发态势能面,根据计算得到的势能面,对相应的基态和激发态反应途径进行了讨论,得到有价值的结论。 展开更多
关键词 σ键迁移 H-H理论 氮叶立德 势能面
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非绝热电子跃迁中的驰豫现象与共振态
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作者 许宗荣 田之悦 《成都科技大学学报》 EI CAS CSCD 1995年第1期26-30,共5页
用量于力学方法描写非绝热电子跃迁过程.导出并求解了跃迁几率振幅的运动方程,该方程正确描写了共振态的存在和驰豫现象。
关键词 非绝热电子跃迁 共振态 驰豫 跃迁几率 量子化学
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