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A Singlet State Generated with SQUIDs in Cavity QED
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作者 谢琳 陈立波 顾永建 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第12期1003-1006,共4页
We propose a scheme to generate a three-qubit three-IeveI singlet state in cavity QED, by placing three A-type SQUIDs in a single mode cavity. In this scheme, we make use of the interaction between the SQUIDs and cavi... We propose a scheme to generate a three-qubit three-IeveI singlet state in cavity QED, by placing three A-type SQUIDs in a single mode cavity. In this scheme, we make use of the interaction between the SQUIDs and cavity filed, and the classical pulses. The cavity fields are in vacuum state during the whole operation processes of creating the entanglement, and there is no quantum information transformation between the SQUIDs and cavity fields. Because of the advantage of the SQUID-cavity system, the quality factor of the cavity is greatly relaxed. 展开更多
关键词 singlet state SQUID CAVITY ENTANGLEMENT
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Structure of Essential Spectra and Discrete Spectrum of the Energy Operator of Six-Electron Systems in the Hubbard Model. First Quintet and First Singlet States
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作者 S. M. Tashpulatov 《Journal of Applied Mathematics and Physics》 2022年第11期3424-3461,共38页
We consider the energy operator of six-electron systems in the Hubbard model and investigate the structure of essential spectra and discrete spectrum of the system in the first quintet and first singlet states in the ... We consider the energy operator of six-electron systems in the Hubbard model and investigate the structure of essential spectra and discrete spectrum of the system in the first quintet and first singlet states in the v-dimensional lattice. 展开更多
关键词 Hubbard Model Essential Spectrum Discrete Spectrum Six Electron Systems Octet state singlet state Quintet state
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Generation of Three-Qutrit Singlet States with Two-Level Trapped Ions
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作者 杨榕灿 叶丽香 +1 位作者 林秀 陈翔 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第10期391-394,共4页
We propose an adiabatic-passage scheme for the generation of three-qutrit singlet states with two-level trapped ions. Distinctly different from previous proposals, we encode qutrits in Dicke states with two-level ions... We propose an adiabatic-passage scheme for the generation of three-qutrit singlet states with two-level trapped ions. Distinctly different from previous proposals, we encode qutrits in Dicke states with two-level ions and use the adiabatic-evolution techniques in order not to exactly control the laser pulses, making the realization of the scheme much easier. Furthermore, the phonon is only virtually excited in the procedure, so the effect of the phonon losses can be reduced. 展开更多
关键词 singlet states ADIABATIC PASSAGE TRAPPED ions
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Disentanglement of a Singlet Spin State in a Coincidence Stern-Gerlach Device
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作者 Per-Olof Westlund +1 位作者 kan Wennerstrô m 《Journal of Modern Physics》 2019年第10期1247-1254,共8页
We analyze the spin coincidence experiment considered by Bell in the derivation of Bells theorem. We solve the equation of motion for the spin system with a spin Hamiltonian, Hz, where the magnetic field is only in th... We analyze the spin coincidence experiment considered by Bell in the derivation of Bells theorem. We solve the equation of motion for the spin system with a spin Hamiltonian, Hz, where the magnetic field is only in the z-direction. For the specific case of the coincidence experiment where the two magnets have the same orientation the Hamiltonian Hz commutes with the total spin Iz, which thus emerges as a constant of the motion. Bells argument is then that an observation of spin up at one magnet A necessarily implies spin down at the other B. For an isolated spin system A-B with classical translational degrees of freedom and an initial spin singlet state there is no force on the spin particles A and B. The spins are fully entangled but none of the spin particles A or B are deflected by the Stern-Gerlach magnets. This result is not compatible with Bells assumption that spin 1/2 particles are deected in a Stern-Gerlach device. Assuming a more realistic Hamiltonian Hz + Hx including a gradient in x direction the total Iz is not conserved and fully entanglement is not expected in this case. The conclusion is that Bells theorem is not applicable to spin coincidence measurement originally discussed by Bell. 展开更多
关键词 Bells THEOREM DISENTANGLEMENT Stern-Gerlach Coincident Measurement singlet Spin state
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Synthesis and photochemistry of novel bromo substituted stilbene derivatives as triplet state sensitizers for the generation of singlet oxygen
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作者 Hong Ru Li Qin Yuan Guo Ting Xie Fang Gao Sheng Tao Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第12期1415-1418,共4页
We have presented the synthesis and characterization of three new bromo substituted stilbene derivatives, p-3,4,5-trimethoxy-p′- 2,3,4,5,6-pentabromostilbene (C1), p-N,N-dimethylamino-p′-2,3,4,5,6-pentabromostilbe... We have presented the synthesis and characterization of three new bromo substituted stilbene derivatives, p-3,4,5-trimethoxy-p′- 2,3,4,5,6-pentabromostilbene (C1), p-N,N-dimethylamino-p′-2,3,4,5,6-pentabromostilbene (C2) and p-N,N-diphenylamino-p′- 2,3,4,5,6-pentabromostilbene (C3) in this letter. The UV/vis absorption and photoluminescence were investigated in various solvents. The maximal absorption wavelength of C1 exhibited blue-shift to those of C2 and C3 in different solvents. No florescence emission could be detected for these compounds at room temperature. Singlet oxygen could be efficiently produced with these sensitizers under near-ultraviolet and visible light irradiation. 展开更多
关键词 SYNTHESIS PHOTOCHEMISTRY Triplet state Bromo substitution singlet oxygen
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Spectra of the Energy Operator of Four-Electron Systems in the Impurity Hubbard Model. Triplet State 被引量:1
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作者 S. M. Tashpulatov R. T. Parmanova 《Journal of Applied Mathematics and Physics》 2021年第11期2776-2795,共20页
We consider the energy operator of four-electron systems in an impurity Hubbard model and investigated the structure of essential spectra and discrete spectrum of the system in the first triplet state in a one-dimensi... We consider the energy operator of four-electron systems in an impurity Hubbard model and investigated the structure of essential spectra and discrete spectrum of the system in the first triplet state in a one-dimensional lattice. For investigation the structure of essential spectra and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model, for which the momentum representation is convenient. In addition, we used the tensor products of Hilbert spaces and tensor products of operators in Hilbert spaces and described the structure of essential spectrum and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model. The investigations show that there are such cases: 1) the essential spectrum of the system consists of the union of no more than eight segments, and the discrete spectrum of the system consists of no more than three eigenvalues;2) the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues;3) the essential spectrum of the system consists of the union of no more than three segments, and the discrete spectrum of the system is the empty set. Consequently, the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues. 展开更多
关键词 Hubbard Model Essential Spectrum Discrete Spectrum Four Electron Systems Quintet state Triplet state singlet state SPECTRA
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Four-Electron Systems in the Impurity Hubbard Model. Second Triplet State. Spectra of the System in the ν-Dimensional Lattice Zν
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作者 S. M. Tashpulatov R. T. Parmanova 《Journal of Applied Mathematics and Physics》 2023年第11期3393-3427,共35页
We consider an energy operator of four-electron system in the Impurity Hubbard model with a coupling between nearest-neighbors. The spectrum of the systems in the second triplet state in a ν-dimensional lattice is in... We consider an energy operator of four-electron system in the Impurity Hubbard model with a coupling between nearest-neighbors. The spectrum of the systems in the second triplet state in a ν-dimensional lattice is investigated. For investigation the structure of essential spectra and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model, for which the momentum representation is convenient. In addition, we used the tensor products of Hilbert spaces and tensor products of operators in Hilbert spaces and described the structure of essential spectrum and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model for the second triplet state of the system. The investigations show that the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues. 展开更多
关键词 Spectra of Four-Electron System Bound state Anti-Bound state Impurity Hubbard Model Quintet state singlet state Triplet state
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Variational Calculations for (ns2) 1Se, (np2) 1De and (nd2) 1Ge Resonance States for He Isoelectronic Sequences below the n = 2, 3 and 4 Hydrogenic Thresholds
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作者 Matabara Dieng 《Journal of Modern Physics》 2023年第12期1617-1633,共17页
This work presents results of the different parameters which characterize the nonrelativistic Hamilton operator for the helium atoms allowing us to solve the Schrödinger equation. The total energy is decomposed i... This work presents results of the different parameters which characterize the nonrelativistic Hamilton operator for the helium atoms allowing us to solve the Schrödinger equation. The total energy is decomposed into three terms allowing to separate the kinetic energy, the electrons-nucleus interaction energy and the electron-electron interaction energy of the (2s<sup>2</sup>, 3s<sup>2</sup> and 4s<sup>2</sup>) <sup>1</sup>S<sup>e</sup>, (2p<sup>2</sup>, 3p<sup>2</sup> and 4p<sup>2</sup>) <sup>1</sup>D<sup>e</sup> and (3d<sup>2</sup> and 4d<sup>2</sup>) <sup>1</sup>G<sup>e</sup> resonance singlet states of the helium isoelectronic sequences. The states have been defined by using special forms of the Hylleraas type wave functions. The calculations have been carried out in the framework of the variational method using configuration interaction basis states with a real Hamiltonian. The agreement of the energy value of other states between the present theoretical values available in the literature is excellent. But as for the comparison of the kinetic energies, the electrons-nucleus energies interaction and the electron-electron interaction energies, we note a slight difference with the theoretical values common in literature. 展开更多
关键词 Hylleraas Method Helium-Like Ions Systems singlet Doubly-Excited states Matrix Elements AUTOIONIZATION
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不同耦合构型多自旋体系单重态制备效率研究 被引量:1
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作者 王子文 辛家祥 +1 位作者 魏达秀 姚叶锋 《波谱学杂志》 CAS 2024年第1期67-76,共10页
核自旋单重态是一种特殊的量子态,其存在寿命能远长于纵向弛豫时间(T1),能够被用于研究分子之间的慢扩散和慢运动等动力学过程.单重态的制备是其能成功应用的关键.目前文献中报道了多种制备单重态的方法,这些方法主要适用于孤立的两自... 核自旋单重态是一种特殊的量子态,其存在寿命能远长于纵向弛豫时间(T1),能够被用于研究分子之间的慢扩散和慢运动等动力学过程.单重态的制备是其能成功应用的关键.目前文献中报道了多种制备单重态的方法,这些方法主要适用于孤立的两自旋体系,当单重态所涉及的核自旋受到其它自旋的耦合作用时,单重态的制备效率往往会降低.本文以三自旋体系为例,研究了不同耦合构型下单重态的制备效率受非单重态自旋耦合的影响,模拟结果表明当单重态自旋由弱耦合逐渐变为强耦合时,单重态的制备效率会在单重态自旋与非单重态自旋的耦合呈现对称性时保持一定的稳定性,此特性能够为复杂体系中选择合适的自旋制备单重态提供参考.我们利用N-乙酰-L-天门冬氨酸(NAA)分子的三个质子组成的自旋体系实验验证了以上结论,通过调节NAA分子的酸碱度,所选的三自旋体系能从弱耦合向强耦合转变,实验结果表明:当三自旋中单重态自旋处于强耦合时,单重态的制备效率明显高于弱耦合时的效率. 展开更多
关键词 核磁共振 核自旋单重态 制备效率 N-乙酰-L-天门冬氨酸 脉冲序列 优化控制
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基于核自旋单重态的活体谷胱甘肽分子MRS信号选择
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作者 朱向炜 杨雪 +1 位作者 魏达秀 姚叶锋 《波谱学杂志》 CAS 2024年第4期373-381,共9页
谷胱甘肽(GSH)是一种由谷氨酸、半胱氨酸和甘氨酸聚合而成的三肽,是人体还原驱动力的主要来源,能维持人体内部氧化还原平衡.谷胱甘肽还与生物体内自由基淬灭、肿瘤治疗密切相关.利用活体磁共振波谱(MRS)监测生物体中谷胱甘肽的含量变化... 谷胱甘肽(GSH)是一种由谷氨酸、半胱氨酸和甘氨酸聚合而成的三肽,是人体还原驱动力的主要来源,能维持人体内部氧化还原平衡.谷胱甘肽还与生物体内自由基淬灭、肿瘤治疗密切相关.利用活体磁共振波谱(MRS)监测生物体中谷胱甘肽的含量变化对于理解其生物学作用具有重要意义.由于生物体内环境复杂,活体组织的磁共振信号往往重叠严重,难以实现特定分子的选择性检测及定量.本文介绍了一种利用核自旋单重态选择性检测活体谷胱甘肽分子的方法,通过在谷胱甘肽中选择合适的自旋体系,将其制备为单重态,借助梯度脉冲消除其它分子的信号,进而实现谷胱甘肽信号的选择性检测.该方法在健康人体大脑中得到了实验验证,理论和实验结果表明,与文献中报道的其它方法相比,本文的方法具有检测效率高、选择性强的特点. 展开更多
关键词 磁共振波谱 谷胱甘肽 分子靶向信号检测 核自旋单重态 优化控制脉冲
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基于单态的量子隐私集合求交协议
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作者 田欣莹 林舒欣 林崧 《安徽大学学报(自然科学版)》 CAS 北大核心 2024年第6期47-54,共8页
隐私集合求交(private set intersection,简称PSI)是一种重要的密码原语.提出基于单态的量子隐私集合求交(quantum private set intersection,简称QPSI)协议.在该协议中,单态作为信息载体由一个半可信第三方制备,两个参与者根据各自的... 隐私集合求交(private set intersection,简称PSI)是一种重要的密码原语.提出基于单态的量子隐私集合求交(quantum private set intersection,简称QPSI)协议.在该协议中,单态作为信息载体由一个半可信第三方制备,两个参与者根据各自的私有数据集将信息编码至载体粒子.参与者在半可信第三方协助下能获得正确的交集,且不会得到交集以外另一方集合的任何信息.该文协议能抵抗一些常见的外部攻击和内部攻击.该文协议可推广至多方情形,具有良好的扩展性。 展开更多
关键词 量子密码 隐私集合求交 单态 FOURIER变换
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单线态裂分中间态的理论研究进展
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作者 童磊 张春峰 《物理学进展》 北大核心 2024年第3期112-122,共11页
单线态裂分是指有机材料在光激发后,从一个单重态激子转变为两个三重态激子的光物理过程。该过程有望提高光电转换效率,因而受到了广泛的关注。研究发现单线态裂分中存在一个关键的中间态,而如何构建中间态的波函数则是重要的挑战。本... 单线态裂分是指有机材料在光激发后,从一个单重态激子转变为两个三重态激子的光物理过程。该过程有望提高光电转换效率,因而受到了广泛的关注。研究发现单线态裂分中存在一个关键的中间态,而如何构建中间态的波函数则是重要的挑战。本文着重介绍了双激发态波函数构建的两类理论模型,而后讨论了振动、轨道和自旋相互作用对中间态形成和解离的影响。最后总结了进一步的理论研究将面临的挑战。 展开更多
关键词 单线态裂分 双激发态 电子态耦合 交换相关能
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凝聚态硝基甲烷分解机理的密度泛函研究 被引量:8
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作者 董光兴 程新路 +1 位作者 葛素红 李德华 《原子与分子物理学报》 CAS CSCD 北大核心 2014年第5期687-694,共8页
用密度泛函理论在B3LYP/6-311++G(2d,2P)计算水平上对最低单态和最低三态的硝基甲烷分子进行了分子动力学计算分析,发现:基态硝基甲烷分子沿C-N键分解生成硝基和甲基反应通道上不存在过渡态,只能是在能量足够高的时候造成C-N键的断裂,... 用密度泛函理论在B3LYP/6-311++G(2d,2P)计算水平上对最低单态和最低三态的硝基甲烷分子进行了分子动力学计算分析,发现:基态硝基甲烷分子沿C-N键分解生成硝基和甲基反应通道上不存在过渡态,只能是在能量足够高的时候造成C-N键的断裂,键离解能为53.4kcal/mol;硝基甲烷分子在最低三态沿C-N键分解生成硝基和甲基的反应通道上,有一个活化能为87.8kcal/mol的能垒.计算得到硝基甲烷分子从基态到最低三态分解反应发生所需要的总能量为144.58kcal/mol.这个数值与硝基甲烷材料的电子碰撞实验在193nm处有强吸收峰的结论相符合.依据多声子迁移理论,结合硝基甲烷分子在最低三态动力学分解的可能性,可以认为在相同条件下,硝基甲烷材料在撞击条件下,分子沿CN键分裂生成硝基和甲基的反应在最低三态分子分解的可能性较大.文章用量化计算从分子构型、频率分析和势能面扫描方面对分析结论进行了加强和确定,并且,依据多声子迁移理论对硝基甲烷分子基态键离解过程、基态到三态激发过程和最低三态活化过程中的声子迁移进行了初步分析. 展开更多
关键词 硝基甲烷(NM) 振动频率 基态 三重态 多声子迁移模型
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非线形CS_2分子单重态和三重态的密度泛函理论 被引量:8
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作者 曹兆华 步宇翔 韩克利 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2004年第4期415-420,共6页
应用密度泛函理论 (DFT)的B3LYP和B3PW91两种方法 ,在 6 3 11+G 和aug cc pVTZ基组水平上 ,分别优化了CS2 可能存在的非线形单重态和三重态构型 ,在全局势能面上共发现 3个单重态 (电子态 1 A1 )和 5个三重态 (电子态分别为 3A2 、3B2 ... 应用密度泛函理论 (DFT)的B3LYP和B3PW91两种方法 ,在 6 3 11+G 和aug cc pVTZ基组水平上 ,分别优化了CS2 可能存在的非线形单重态和三重态构型 ,在全局势能面上共发现 3个单重态 (电子态 1 A1 )和 5个三重态 (电子态分别为 3A2 、3B2 和 3B2 )的非线形CS2 异构体 ,正则振动频率分析证明所得到构型均是位能面上的极小 .计算所得CS2 异构体的相对能量顺序为 4t3B2 <a1 A1 <1t3A2 <3t3B1 <5t3B2 <2t3B1 <b1 A1 <c1 A1 .成键分析表明 。 展开更多
关键词 CS2 单重态 三重态 密度泛函理论
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几种萘酞菁硅配合物的光动力效应的研究 被引量:3
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作者 牛晓宇 朱宇君 +4 位作者 薛金萍 于海燕 吴谊群 陈耐生 黄金陵 《感光科学与光化学》 EI CAS CSCD 2005年第6期407-413,共7页
研究了7种轴向配位的萘酞菁硅配合物的激发态性质、产生单重态氧的能力及对几种氨基酸的光敏氧化能力.研究表明,对于相同浓度的不同配合物来说,随着轴向配位基团推电子能力的逐渐增强,激发三重态寿命降低,产生单重态氧的能力逐渐下降,... 研究了7种轴向配位的萘酞菁硅配合物的激发态性质、产生单重态氧的能力及对几种氨基酸的光敏氧化能力.研究表明,对于相同浓度的不同配合物来说,随着轴向配位基团推电子能力的逐渐增强,激发三重态寿命降低,产生单重态氧的能力逐渐下降,而产生单重态氧的能力是光敏氧化氨基酸反应速率的决定因素,因此,其光敏氧化氨基酸的一级反应速率常数逐渐减小. 展开更多
关键词 萘酞菁硅 激发态 单重态氧 光氧化 氨基酸
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卟吩垂直激发态的理论研究方法的比较 被引量:7
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作者 任彦亮 万坚 +1 位作者 刘俊军 万洪文 《物理化学学报》 SCIE CAS CSCD 北大核心 2004年第9期1089-1092,共4页
运用TDDFT、ZINDO、INDO/S三种量子化学理论方法,对卟吩的单线垂直激发态进行了理论计算与归属研究.研究发现,对于卟吩类大分子而言,ZINDO和INDO/S方法对研究Q带和B带等特征的低能量激发态具有足够的精度,且对高能带也能给出定性的解释... 运用TDDFT、ZINDO、INDO/S三种量子化学理论方法,对卟吩的单线垂直激发态进行了理论计算与归属研究.研究发现,对于卟吩类大分子而言,ZINDO和INDO/S方法对研究Q带和B带等特征的低能量激发态具有足够的精度,且对高能带也能给出定性的解释,可以用于更大的生物发色团分子的垂直激发态的理论研究. 展开更多
关键词 卟吩 单线垂直激发态 理论研究方法 时间相关密度泛函理论 半经验分子轨道理论方法
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三种脉冲序列制备核自旋单重态效率的比较 被引量:1
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作者 李毅 辛家祥 +2 位作者 王嘉琛 魏达秀 姚叶锋 《波谱学杂志》 CAS 北大核心 2021年第2期227-238,共12页
核自旋单重态的制备和检测在化合物分子的相关分析中具有重要的应用价值和广阔的应用前景.本文以三肽分子AGG(Ala-Gly-Gly)中两个质子构成的一组孤立的自旋耦合体系为研究对象,利用三组基于不同原理的脉冲序列,分别对该体系制备了核自... 核自旋单重态的制备和检测在化合物分子的相关分析中具有重要的应用价值和广阔的应用前景.本文以三肽分子AGG(Ala-Gly-Gly)中两个质子构成的一组孤立的自旋耦合体系为研究对象,利用三组基于不同原理的脉冲序列,分别对该体系制备了核自旋单重态;并分别测定和比较了三种方法制备核自旋单重态的效率及其寿命.研究结果表明,对于同一分子的同一自旋耦合体系中的质子,使用不同的脉冲序列制备得到的核自旋单重态的寿命并不会有明显差异,但基于不同脉冲制备核自旋单重态的效率差异相对较大. 展开更多
关键词 核磁共振 核自旋单重态 制备效率 AGG 脉冲序列
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分子单重/叁重混合激发态碰撞传能中的量子干涉效应 被引量:5
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作者 沙国河 张存浩 《物理化学学报》 SCIE CAS CSCD 北大核心 2004年第F08期1010-1016,共7页
量子干涉效应是基于量子力学波粒二象性原理,即微观粒子的运动皆具有波的特性而产生的一种干涉现象,故又称为物质波干涉.近年来,在分子的光激发、光解和光电离及碰撞过程中皆已观察到量子干涉效应,成为分子动态学领域研究热点之一.我们... 量子干涉效应是基于量子力学波粒二象性原理,即微观粒子的运动皆具有波的特性而产生的一种干涉现象,故又称为物质波干涉.近年来,在分子的光激发、光解和光电离及碰撞过程中皆已观察到量子干涉效应,成为分子动态学领域研究热点之一.我们小组在国际上首次得到了单重/叁重混合激发态分子碰撞传能中的量子干涉的实验证据,从理论上导出了包括干涉相位角的传能截面公式,从实验上发展了激光双共振多光子电离光谱技术,用以测定了CO(A1Π,v=0/e3Σ-,v=1)与各种原子(He,Ne,Ar)及双原子分子H2,O2,N2,HCl碰撞传能的干涉角.其后又与李丽的小组合作,在热管炉中用激光双共振诱导荧光法观察到Na2(A1Σ+u,v=8/b3Π0u,v=14)-Na碰撞中的量子干涉效应,证明了碰撞干涉效应的普遍性.近年来,在理论方面,我们发展了基于含时微扰的一级波恩近似量子散射方法,计算出了上述碰撞体系的干涉角θST,与实验值符合极好.本文指出虽然气池实验测得的干涉角θST是不同分子碰撞速度及碰撞参数的“平均”结果,但与理论计算的微分干涉角尚比较接近,可提供激发态分子碰撞相互作用势的重要而难得的信息. 展开更多
关键词 单重-叁重混合态 碰撞传能 量子干涉 光学双共振多光子电离
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Theoretical Study on the Structure and Isomerization of CH_3SB 被引量:1
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作者 杜玉扣 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第3期349-353,共5页
The structure and mechanism of isomerization of CH3SB have been studied by using DFT method at the B3LYP/6-311G** level. The computational results reveal that the energy of singlet state of CH3SB is lower than that ... The structure and mechanism of isomerization of CH3SB have been studied by using DFT method at the B3LYP/6-311G** level. The computational results reveal that the energy of singlet state of CH3SB is lower than that of triplet state, so the former should be the ground state. Two transition states of isomerization of singlet state of CH3SB have been determined at the B3L-YP/6- 311G** level, too. The methyl linked to sulfur atom is first transferring to the boron atom, to which the hydrogen atom of methyl is then transferring. According to the results of this paper, reaction paths of isomerizations of CH3SB are studied thoroughly with IRC method. 展开更多
关键词 DFT CH3SB singlet state ISOMERIZATION IRC
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假根羽藻外周天线LHCⅡ寡聚体的瞬态吸收光谱(英文)
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作者 贺俊芳 朱长军 +1 位作者 赵小侠 李院院 《光子学报》 EI CAS CSCD 北大核心 2014年第8期215-220,共6页
采用时间分辨瞬态吸收光谱技术研究了假根羽藻外周天线寡聚体的光保护机制.分别以667nm飞秒激光脉冲和白光脉冲作为泵浦光和探测光,探测光与泵浦光之间的延时范围和准确度分别为340ps和134fs.实验结果表明在泵浦光激发之后外周天线... 采用时间分辨瞬态吸收光谱技术研究了假根羽藻外周天线寡聚体的光保护机制.分别以667nm飞秒激光脉冲和白光脉冲作为泵浦光和探测光,探测光与泵浦光之间的延时范围和准确度分别为340ps和134fs.实验结果表明在泵浦光激发之后外周天线对探测光的吸收是动态变化的.对瞬态吸收光谱进行多指数拟合,并结合外周天线的荧光发射谱和激发谱进行分析,结果表明:500~600am的瞬态吸收谱主要来源于类胡萝卜素分子,外周天线寡聚体至少包含四种具有光保护作用的类胡萝卜素分子,对应的S0→Sn跃迁光谱为511nm和55413.111,522nm和541nm,530nm和563nm(对应管藻黄素),536nm和575nm;类胡萝卜素分子以两种方式参与到光保护过程中:一种是直接方式,在几皮秒范围内猝灭叶绿素三重态;另一种是间接方式,在几百皮秒范围内猝灭从叶绿素分子获得能量的单线态氧. 展开更多
关键词 瞬态吸收光谱 光合作用 泵浦探测 外周天线 光保护 类胡萝卜素 叶绿素 单线态氧
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