搜索

x
中国物理学会期刊

基态S和D原子的低能弹性碰撞及SD(X2Π)自由基的准确相互作用势与分子常数

CSTR: 32037.14.aps.58.7646

Elastic collision between S and D atoms at low temperatures and accurate analytic interaction potential and molecular constants of the SD(X2Π) radical

CSTR: 32037.14.aps.58.7646
PDF
导出引用
  • 使用Gaussian03程序包提供的CCSD(T)理论及Duning等的相关一致基cc-pVnZ和aug-cc-pVnZ (n=2, 3, 4, 5), 对SD(X2Π)自由基的平衡核间距、谐振频率及相互作用势进行了计算, 并拟合出了相应的光谱常数. 在CCSD(T)/aug-cc-pV5Z理论水平下, 光谱常数D0, De, R

     

    The equilibrium internuclear separations, harmonic frequencies and interaction potentials have been calculated by employing the CCSD(T) theory in combination with the series of the correlation- consistent basis sets, cc-pVnZ and aug-cc-pVnZ (n=2, 3, 4, 5), of Dunning and co-workers. The potential energy curves are all fitted to the Murrell-Sorbie functions, which are used to determine the spectroscopic parameters. At the CCSD(T)/aug-cc-pV5Z level of theory, the values of D0, De, Re, ωe, αe, B0 are 3.65730 eV, 3.77669 eV, 0.13424 cm-1, 1938.372 cm-1, 0.09919 cm-1, 4.88585 cm-1 and 4.8872 cm-1, respectively, which conform almost perfectly with the available measurements. With the analytic interaction potential obtained at the CCSD(T)/aug-cc-pV5Z level of theory, a total of 23 vibrational states has been predicted for the first time when the rotational quantum number J is set to equal zero (J=0) by solving the radial Schrdinger equation of nuclear motion. The complete vibrational levels, classical turning points, inertial rotation and centrifugal distortion constants are reproduced from the SD(X2Π) potential when J=0 The total and various partial-wave cross sections are calculated for the elastic collisions between the ground-state S and D atoms at energies from 1.0×10-11 to 1.0×10-4 a.u. when the two atoms approach each other along the SD(X2Π) interaction potential. No shape resonances can be found in the total elastic cross sections. The results show that the shape of the total elastic cross sections is mainly dominated by the s-partial wave at very low temperatures. Because of the weakness of the shape resonances coming from various partial waves, they are all covered up by the strong total elastic cross sections.

     

    目录

    /

    返回文章
    返回