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21.
本文通过对原子—分子散射的全Green算子的恰当数学处理,推导出了GES和GAN理论的跃迁矩阵元表达式,并对其物理意义加以说明,最后列出了用GES理论对He—H_2体系计算结果。  相似文献   
22.
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   
23.
原子刚性转子散射几率的密耦合波包法计算   总被引:1,自引:0,他引:1       下载免费PDF全文
本文分别在方向固定于空间的质心坐标系(以下简称SF坐标系)和随体坐标系(以下简称BF坐标系)两种坐标系中,详细地讨论了最近发展起来的密耦合波包理论,以He-H2为碰撞体系,计算了其态-态跃迁几率,结果表明:(1)在两种坐标系中建立的理论是等价的,其计算结果与标准的密耦合(以下简称CC)法计算的结果符合良好;(2)如果耦合项数增加,则在BF坐标系中密耦合波包法的计算效率将明显高于在SF坐标系中密耦合波包法的计算效率。 关键词:  相似文献   
24.
任廷琦 《中国物理》1999,8(6):434-436
Accurate reactive scattering calculations of reactive probabilities and integral cross sections for the system D+H2→DH+H were carried out by using the quantum mechanical time-dependent wave packet methods. In order to simplify the calculation, we introduced the centrifugal sudden approximation to reduce the effective degrees of freedom, and show results of new calcul ations. In particular, the present calculations were extended to all angular momentum and obtained reaction cross sections for a range of energies. The results were also compared with those of other theoretical calculations and the differences were discussed.  相似文献   
25.
本文采用准经典轨线方法,在LEPS势基础上计算了Ca+CH3I→CaI+CH3在不同碰撞能下的矢量相关计算了质心系中四个广义极化微分反应截面(2π/σ)(dσ00/dωt),(2π/σ)(dσ20/dωt),(2π/σ)(dσ22+/dωt),(2π/σ)(dσ21-/dωt),k-j′两矢量相关的P(θr)分布、k-k′-j′三矢量相关的极角分布P(φr)以及用θr和φr表示的产物转动角动量的空间分布P(θr,φr).  相似文献   
26.
李洪奇  任廷琦  张运海  徐兴磊 《中国物理 B》2012,21(1):10305-010305
A new kind of four-mode continuous variable coherent-entangled state is proposed in the Fock space by using the technique of integration within an ordered product, which exhibits both the properties of a coherent state and an entangled state, and spans a complete and orthonormal representation. The conjugate state of the four-mode continuous variable coherent-entangled state is derived by using the Fourier transformation. Moreover, a simple experimental protocol of generating a four-mode continuous variable coherent-entangled state is proposed by using beam splitters. As applications of this four-mode continuous variable coherent-entangled state, a four-mode entangled state and a four-mode squeezing-Fresnel operator are constructed.  相似文献   
27.
MRCI计算研究B2+分子的结构和解析势能函数   总被引:1,自引:0,他引:1       下载免费PDF全文
采用从头计算的多参考组态CI方法(MRCI) 和B原子Dunnings相关调和基函数含扩散基的大基组aug-cc-pVQZ对B+2分子的基态和低激发态的势能曲线进行计算 .利用Huxley函数、Murrell-Sorbie函数和最小二乘法拟合出了解析势能函数,并以此为基础计算出光谱常数.通过比较发现:Huxley 函数比MS函数的拟合方差更小,能更好地再现分子中原子间相互作用.采用两种函数所得解析势能函数与从头计算势能曲线间的误差RMS 均远小于化学精度4.184 kJ/mol的要求,表明所得解析势能函数很好地再现了这些态中原子间的相互作用情况,可用于更广泛的研究.  相似文献   
28.
A distorted wave procedure is employed to correct the centrifugal sudden wave packet approximation, and the accurate results compared with the standard close coupling method for m-dependent integral cross sections for short- and long- range Ar+N2 potentials at E=O.O258eV are obtained only by using the second-order corrections to the CSWP wave function.  相似文献   
29.
The behavior of ion-beam-induced crystallization of a buried amorphous layer created by means of MeV Si+ irradiation at 300℃ in Si(100) was studied by Rutherford backscattering and channeling technique. Sohd phase epitaxial crystallizations occurred from both the front and the back amorphous-crystalline(a/c) interfaces with the growth thickness being increased linearly with increasing dose of the annealing ion beam, Nuclear energy deposition was proved to play a dominant role in the process of ion-beam-induced crystallization. The high density of electronic excitation, which could enhance defect production near or at the a/c interface, may thus enhance the nuclearly normalized growth rate of ion-beam-induced crystallization at the front a/c interface.  相似文献   
30.
张晓燕  杨传路  高峰  任廷琦 《中国物理》2006,15(9):1981-1986
The multi-reference configuration interaction method and aug-cc-pvqz (AVQZ) have been used to calculate potential energy curves (PECs) of the singlet and triplet states of the riu and rig symmetry of B2++. All of the four states (^l∏u, ^1∏g, ^3∏u and ^3∏g) are found to be metastable states, though the potential well of ^3∏u symmetry is very shallow. Based on the PECs, the analytical potential energy functions (APEFs) of these states have been fitted using the least square fitting method and two models of function. The spectroscopic parameters of each state are also calculated, and are compared with other investigations in the literature. The credibility and veracity of the two functions are evaluated. Some ideas to improve the fitting accuracy are presented. Also the vibrational levels for each state are predicted by solving the SchrSdinger equation of nuclear motion.  相似文献   
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