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41.
Employing the quasi-classical trajectory method and the potential energy surface of Panda and Sathyamurhy [Panda A N and Sathyamurthy N 2004 J.Chem.Phys.121 9343],the effect of the reagent vibration on vector correlation of the ion-molecule reactions D~-+H2 and H~-+D2 is studied at a collision energy of 35.7 kcal/mol.Four generalized polarization-dependent differential cross sections (2π/σ)(dσ 00 /dωt),(2π/σ)(dσ 20 /dωt),(2π/σ)(dσ 22+ /dωt),and (2π/σ)(dσ 21 /dωt) are presented in the centre-of-mass reference frame,separately.At the same time,the effects on the product angular distributions P (θr),P (φr) and P (θr,φr) of the title reactions are also analysed.The calculated results show that the scattering tendencies of the product HD,the alignment and the orientation of j sensitively depend on reagent molecule vibration.  相似文献   
42.
安义鹏  杨传路  王美山  马晓光  王德华 《中国物理 B》2010,19(11):113404-113404
Using density functional theory and quantum transport calculations based on nonequilibum Green’s function formalism,we investigate the charge transport properties of endohedral M@C 20 (M=Na and K) metallofullerenes.Our results show that the conductance of C 20 fullerene can be obviously improved by insertion of alkali atom at its centre.Both linear and nonlinear sections are found on the I-V curves of the Au-M@C 20-Au two-probe systems.The novel negative differential resistance behaviour is also observed in Na@C 20 molecule but not in K@C 20.  相似文献   
43.
采用全量子理论,对注入腔内的二能级原子、单模腔场和振动边界(视为频率为ωm的量子谐振子)构成的系统,在相互作用绘景中,求解了该系统的态函数随时间的演化关系,在此基础上得到了原子布居数随时间的演化关系,结果显示布居数在初始值附近振荡,这说明边界的振动是周期性的,它对原子布居数的影响也是周期性的. 关键词: 边界振动的微腔 二能级原子 布居数  相似文献   
44.
采用多参考组态相互作用方法计算了ZnHg二聚体两个低激发Ⅱ态(1Ⅱ,3Ⅱ)的原子间相互作用势能曲线.用Murrel-Sorbie函数拟合得到了相应的解析势能函数,并用其计算力常数,进而确定了光谱常数.所得结果与仅有的理论工作进行了比较.基于所得势能曲线,通过解分子中原子核运动的薛定谔方程预测了各电子态的振动能级.  相似文献   
45.
在QCISD/6-311G*水平上研究了B+4分子的各种稳定构型. 首先通过从头计算优化出可能的稳定构型, 再通过振动频率的计算判断所得构型是局部极小或鞍点. 同时讨论了Jahn-Teller效应. 通过比较发现从头计算得到的各种构型与群论的结果一致, 并得出一些文献中报道的构型实际上是鞍点. 首次报道了非平面的C2v 构型.  相似文献   
46.
推导了用对比参数表示的平衡蒸汽压力方程和平衡蒸汽密度方程,这些方程适用于D2在临界点以下的行为,计算表明,用对比状态计算露点温度下的蒸汽密度比露点法准确,用BWR方程计算充气压力比用理想气体方程合理。  相似文献   
47.
One-dimensional chain structures of Bn(n=6-16) are calculated by employing a 6-311 G^* basis set.The present calculations show that all the chain structures of interest have local minima with large binding energy per atom and short bond length.It is also found that many previous reported structures of B6 and B7 clusters are saddle points and the one-dimensional chain structures are the corresponding ground-state structures of B6 and B7 clusters.  相似文献   
48.
A full-dimensional analytical potential energy surface(APES) for the F + CH4 →HF + CH3 reaction is developed based on 7127 ab initio energy points at the unrestricted coupled-cluster with single,double,and perturbative triple excitations.The correlation-consistent polarized triple-split valence basis set is used.The APES is represented with a many-body expansion containing 239 parameters determined by the least square fitting method.The two-body terms of the APES are fitted by potential energy curves with multi-reference configuration interaction,which can describe the diatomic molecules(CH,H2,HF,and CF) accurately.It is found that the APES can reproduce the geometry and vibrational frequencies of the saddle point better than those available in the literature.The rate constants based on the present APES support the experimental results of Moore et al.[Int.J.Chem.Kin.26,813(1994)].The analytical first-order derivation of energy is also provided,making the present APES convenient and efficient for investigating the title reaction with quasiclassical trajectory calculations.  相似文献   
49.
The potential energy curves (PECs) of the 3Π states of GaX (X=F, Cl, and Br) molecules are calculated using the multireference configuration interaction method with a large contracted basis set aug-cc-pV5Z. The PECs are accurately fitted to analytical potential energy functions (APEFs) using the Murrell–Sorbie potential function. The spectroscopic parameters for the states are determined using the obtained APEFs, and compared with the theoretical and experimental data available presently in the literature.  相似文献   
50.
陈保栋  杨传路  王美山  马晓光 《中国物理 B》2012,21(8):83103-083103
Encapsulation of biomolecules inside a carbon nanotube(CNT) has attracted great interest because it could enable the delivery of nanoscale pharmaceutical drugs with CNT-based devices.Using a molecular dynamics simulation,we investigate the dynamic process by which human immunodeficiency virus(HIV) replication inhibitor peptides(HRIPs) are encapsulated in a water solution contained inside a CNT.The van der Waals attraction between the HRIPs and the CNT and the root-mean-square deviation are used to analyse the evolution of the encapsulation.It is found that the interaction between the HRIPs and the CNT is the main driving force for the encapsulation process,which does not cause an obvious conformational change to the HRIPs.  相似文献   
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