几何活性原子态的计算

通过广义的Laguerre类型轨道,在组态相互作用框架内,发展了一套从头计算程序,来研究原子中的电子结构.应用该程序,通过计算能量最小值,求出最优波函数.利用优化波函数的单电子密度分布和角双电子密度的最可几分布,研究了处于最低激发态的Be,B,C,N,O,Ne原子的sαpβ组态的几何活性原子态GAAS(geometricallyactive atomic state).结果显示,作为原子波函数的内禀性质,双电子密度最可几角分布的角度与通常由分子杂化轨道理论解释的相关原子的分子的结合键角近似相等.     

非Born-Oppenheimer近似一对双原子分子振动光谱的修正

为提高Born-Oppenheimer(BO)近似的精确度,修正BO近似所得到的令人不太满意的结果,此文在电子与原子核之间引入一个位相差,并利用小参数微扰法推导出了双原子分子核振动的波函数及红外能谱的计算公式,由修正后的结果得到的双原子分子红外振动光谱线的位置应更接近于实验观测值.     

NO分子γ系(A~2∑~ X~2∏_r振子强度的理论计算

选用STO-4G双ξ加键函数的扩展基组,先取一部分组态用MCSCF方法计算分子轨道,然后再作较大规模的CI计算,得到HO分子基电子态和第一激发电子态的波函数。在偶极近似下,计算了NO分子r系的振子强度,其值为0.00214,与实验值相符甚好。本文的计算方法原则上可用于所有开壳层或闭壳层结构的双原子分子或电离的双原子分子的理论计算。     

苯环分子的分子轨道计算

本文在分子轨道法和分子轨道的原子线性组合法的基础上采用huckel近似,对苯环的分子轨道波函数进行了计算,得出了苯环的6个π键的原子轨道波函数和本征值。     

SiH_4、PH_3、H_2S、HCl分子的单中心球对称波函数与能量的变分计算

本文选用类Ar原子的波函数近似地作为SiH_4,PH_3,H_2S,HCl分子的单中心球对称电子波函数。在单中心球模型近似下,用变分法确定出了SiH_4,PH_3,H_2S,HCl分子的电子波函数最佳参数值,并计算了分子基态总能量。我们计算出的分子基态能量接近于SCFMO法计算结果。这样可使复杂问题的处理得到了大大简化。     

BS分子a带系A^2П→X^2∑＋及γ带系C^2П→X^2∑^＋法兰克—康登因子？…

在双原子分子核运动的薛定谔方程中，计入分子的振转相互作用项，在Ｍ势近似下得出的波函数除与振动量子数有关外，不写转动量子数有关。本和该波函数编程了ＢＳα带系Ａ＾２П→Ｘ＾２∑＾＋法兰克－康登因子。计算中转动量子数的取值由Ｊ＝０至Ｊ＝２００，其结果适用于低温、高温和强激波条件。     

利用近似理论计算原子分子形状因子的平方

实现了基于近似理论数值计算原子基态形状因子平方的方法,并以氢原子为例,检验了Hatree-Fock近似方法与密度泛函近似方法的优劣,对比了不同基组的精确性.这种数值计算方法也适用于揭示其他波函数无法精确求解的原子和分子的电子结构.     

一维双势阱问题的理论研究

利用数值计算的方法求解了一维理想双势阱模型的基态及低激发态能级和相应的波函数,将双势阱之间的间距、双势阱的相对深度和双势阱的宽窄与实际的物理问题建立了联系,并分析了它们对一维双势阱的能级和相应波函数的影响,定性地模拟了双原子分子和原子中的双势阱问题.     

基态波函数对氦原子双电离微分截面的影响

文中采用氨原子的三种近似波函数,计算了入射电子能量为5599 eV时,敲出电子共面等能分享几何安排下,氦原子双电离He(e,3e)反应全微分截面.结果表明三种波函数的理论计算结果,在误差范围内都与实验数据基本吻合,其中采用Pluvinage波函数所得到的理论数据更接近实验数据.     

基态波函数对氦原子双电离微分截面的影响

文中采用氦原子的三种近似波函数,计算了入射电子能量为5599eV时,敲出电子共面等能分享几何安排下,氦原子双电离He（e,3e）反应全微分截面.结果表明三种波函数的理论计算结果,在误差范围内都与实验数据基本吻合,其中采用Pluvinage波函数所得到的理论数据更接近实验数据.     

A new approximation method to obtain vibration eigenfunctions suitable for a new oscillator model

A new oscillator model has been proposed by introducing some modifications in the Morse potential function. Its efficacy is tested by taking a number of electronic states of diatomic molecules. For comparison the Hulbert-Hirschfelder model potential is also used. A new approximation method to find the vibrational eigenfunctions suitable for the new oscillator model has been reported. Langer’s method has been used to determine the wavefunctions. Franck-Condon factors andr-centroids are reported for the observed bands ofD ¹Π —X ¹Σ system of SnO molecule.     

An optimization analysis on the molecular vibrational energy eigenvalues of a diatomic gasdynamic laser

We study briefly the eigenvalue spectrum corresponding to the vibrational-energy levels of the molecules as anharmonic oscillators in a diatomic gasdynamic laser by calculating the maximum eigenvalue when all the possible diatomic configurations are considered within the context of gasdynamic lasers. In this context, a parameter which characterizes the anharmonicity of a given diatomic molecule as a one-dimensional oscillator is used in our calculations.     

q变形振子模型描述的双原子分子的能级数与离解能

本文利用q变形振子模型,导出了双原子分子的势阱总能级数和离解能公式。实际计算表明,q振子模型计算的离解能,略大于实验值,误差平均约为10％,优于常用的Birge-Sponer外推法,可作为一种估算离解能的新方法。 关键词：     

Simple formula for the ionization rate of diatomic molecules in an intense laser field using the velocity gauge

We derive a general ionization rate formula for the system of diatomic molecules in the velocity gauge. A more concise expression of the photoionization rate in the tunnel region is obtained for the first time. Comparisons are made among the different versions of strong-field approximation. The numerical study shows that the ionization rate in the velocity gauge is underestimated by a few orders compared with that in the length gauge. Our simple formula of ionization rate may provide an insight into the ionization mechanism for the system of diatomic molecules.     

激光对双原子分子自发辐射的影响

在偶极近似下，研究了激光场中双原子分子的修饰态（ｄｒｅｓｓｅｄ ｓｔａｔｅ），讨论了修饰态之间的自发辐射；与没有激光时相应过程比较，结果表明激光影响下荧光呈多重结构。     

Unique definitions for the band strength and the electronic-vibrational dipole moment of diatomic molecular radiative transitions

Unique definitions of the band strength and the electronic-vibrational dipole moment are inferred from a recently published fundamental discussion on the line strength of rotational transitions in diatomic molecules. In addition, consistent relations between these quantities and the transition probability or oscillator strength are presented.     

The rotation–vibration spectrum of diatomic molecules with the Tietz–Hua rotating oscillator and approximation scheme to the centrifugal term

The Tietz–Hua (TH) potential is one of the very best analytical model potentials for the vibrational energy of diatomic molecules. By using the Nikiforov–Uvarov method and Pekeris approximation to the centrifugal term, we have obtained the solutions of the radial Schrödinger equation for the TH potential. The energy eigenvalues and corresponding eigenfunctions are calculated in closed form. Some remarks and numerical results are also presented for some diatomic molecules.     

基于核运动效应下的H同位素双原子分子的解析势能函

在加入核运动效应修正下的Born-Oppenheimer近似电子能量的基础上, 采用QCISD(T)/ aug-cc-pvqz方法计算出H同位素双原子分子（H₂, HD, HT, D₂, DT,T₂）的势能函数参数, 获得体现H同位素分子质量差异下的势能函数。 并在此基础上导出H同位素分子的力常数和光谱数据。 同时对于OH, OD和OT分子采用QCISD/aug-cc-pvtz方法计算, 同样获得了这些分子对应的势能函数、 力常数和光谱数据。Based on the correction of the electron energy under Born Oppenheimer approximation using nuclear motion effect, the parameters of potential energy functions for hydrogen isotopic diatomic molecules (H₂, HD,HT,D₂, DT,T₂) are calculated with QCISD (T) method and aug-cc-pvqz basis set,and those potential energy functions that indicate the differences from the masses of hydrogen isotopic atoms are obtained. The force constants and spectroscopic data of those molecules are calculated as well. The potential energy functions, force constants, and spectroscopic data of the isotopic diatomic molecules OH, OD,and OT are also derived using QCISD method and aug-cc-pvtz basis set.     

Selection rules for electric multipole transition of diatomic molecule in scattering experiments

The knowledge of the energy level structures of atoms and molecules is mainly obtained by spectroscopic experiments.Both photoabsorption and photoemission spectra are subject to the electric dipole selection rules(also known as optical selection rules). However, the selection rules for atoms and molecules in the scattering experiments are not identical to those in the optical experiments. In this paper, based on the theory of the molecular point group, the selection rules are derived and summarized for the electric monopole, electric dipole, electric quadrupole, and electric octupole transitions of diatomic molecules under the first Born approximation in scattering experiments. Then based on the derived selection rules, the electron scattering spectra and x-ray scattering spectra of H2, N2, and CO at different momentum transfers are explained, and the discrepancies between the previous experimental results measured by different groups are elucidated.     

Dynamical aspects of two-molecule collision process in a diatomic gasdynamic laser

A dynamical analysis on the basic collision process between two molecules is presented within the context of diatomic gasdynamic lasers. In particular, the kinetic energy of the colliding molecules resulting from the process above is considered for quite highly excited bound states from a quasi-classical point of view. In this analysis, the magnitude of molecule velocity is calculated and discussed in terms of the anharmonicity of a given molecule as a quantum anharmonic oscillator.