应用CASSCF方法精确计算OH分子A~2∑~+态势能曲线

应用Gaussian03程序包中提供的完全活性空间自洽场(CASSCF)方法,采用多种标准基组对OH分子A~2∑~+态的几何结构进行了优化和势能曲线计算、并将计算结果拟合成了解析的Murrell-Sorbie函数.利用得到的解析势能函数进一步计算了该态的光谱常数,并与实验结果进行了比较.此外,本文还给出了一种新的活性空间的选择方法.     

Scattering properties of the ultracold 133Cs2 triplet state

The elastic scattering properties of ultracold 133Cs2 triplet state are investigated in detail.We construct a potential curve of the 133Cs2 triplet state,based on the latest ab initio molecular potential data and show how the scattering parameters are obtained by using three methods:the Numerov method,the semiclassical method and the variable phase method,where the scattering lengths of the 133Cs2 triplet state,i.e.301.79a0,300.67a0 and 310.81a0 are obtained respectively,with a0 being the Bohr radius.We also calculate the effective range and the number of bound states for the 133Cs2 triplet state.Our results are in agreement with the recent experimental data and the theoretical calculations.This confirms that the results of the scattering properties of the ultracold 133Cs2 triplet state,calculated by using these three methods,are reliable.     

应用变相法研究超冷镁原子的弹性散射特性

本文基于参考文献[5]构建的精确的基态Mg_2的势能曲线,应用变相法对超冷温度下Mg原子的弹性散射特性进行了系统的研究.计算得到Mg原子碰撞的散射长度和有效力程分别为25.9a_0和191.3a_0,其中a_0是玻尔半径;低能极限下镁原子间的弹性碰撞主要为s-波碰撞,同时计算得到的基态Mg_2支持束缚态的数目为19.计算结果与文献[5]和Numerov法所得结果一致.     

Calculation of the elastic collision properties of Na and Li atoms at ultracold temperature

This paper firstly reports a theoretical study of elastic scattering properties in a mixture of ²³Na and ⁷Li atoms at cold and ultracold temperatures in detail. Based on the new constructed accurate singlet X¹∑_g⁺ and the triplet a³∑_u⁺ states interatomic potentials for ²³Na⁷Li mixture, it calculates the scattering lengths and the effective ranges by three computational methods, and obtains good agreements. Using the mass scaling method, it also calculates ²³Na⁶Li scattering lengths and s-wave and total elastic cross sections, whose rich resonance structures were found and interpreted in terms of quasibound diatomic levels trapped behind a centrifugal barrier.     

Variable Phase Method Used to Calculate Ultracold Scattering Properties of 7Li33Cs

Elastic scattering properties of singlet and triplet states of ^7 Li^133 Cs at ultralow temperatures are calculated using the constructed potential curves gleaned from high-precision spectroscopy measurement. We show how to reach the scattering length and the number of bound states via the vaxiable phase method. The scattering lengths of the singlet and triplet states of^7 Li^133 Cs are 50.5 a.u. and -135.7 a.u., respectively. We derive two corrections, arising from long range interactions, accurately to at least first order, which provide upper and lower computed bounds to the scattering length. Our results are consistent with the recent experimental data and the theoretical calculation.     

应用CASSCF方法精确计算OH分子 A(2)^Σ^(+) 态势能曲线

应用 Gaussian03 程序包中提供的完全活性空间自洽场 (CASSCF) 方法, 采用多种标准基组对 OH 分子A(2)^Σ^(+)态的几何结构进行了优化和势能曲线计算、并将计算结果拟合成了解析的 Murrell-Sorbie 函数。利用得到的解析势能函数进一步计算了该态的光谱常数，并与实验结果进行了比较。此外，本文还给出了一种新的活性空间的选择方法。     

BH 分子 Χ1Σ+ 和 B1Σ+ 态的理论研究

本文应用 Gaussian03 程序包中提供的完全活性空间自洽场 (CASSCF) 方法, 采用标准基组 6-311++G(3d,2p) 对 BH 分子Χ1Σ+ 和 B1Σ+ 态势能曲线进行了单点能计算. 在此基础上, 利用相关理论将计算结果拟合到 Murrell-Sorbie 函数得到了与各电子态相对应的光谱常数和力常数, 并将计算结果与实验和其他理论结果进行了比较. 同时, 我们还利用光谱常数与力常数以及 Murrell-Sorbie 函数之间的关系计算了与实验光谱数据相对应的力常数和 Murrell-Sorbie 函数, 并与 CASSCF 结果进行了比较得出了一些有价值的结论. 最后, 对于具有双极小值的B1Σ+ 态给出了更精确的定量的信息.     

BH分子X1∑+和B1∑+态的理论研究

本文应用 Gaussian03 程序包中提供的完全活性空间自洽场 (CASSCF) 方法,采用标准基组 6-311++G(3d,2p) 对 BH 分子X1∑+和B1∑+态势能曲线进行了单点能计算.在此基础上,利用相关理论将计算结果拟合到 Murrell-Sorbie函数得到了与各电子态相对应的光谱常数和力常数,并将计算结果与实验和其他理论结果进行了比较.同时,我们还利用光谱常数与力常数以及 Murrell-Sorbie函数之间的关系计算了与实验光谱数据相对应的力常数和 Murrell-Sorbie 函数,并与CASSCF结果进行了比较得出了一些有价值的结论.最后,对于具有双极小值的B1∑+态给出了更精确的定量的信息.