中国物理B ›› 2009, Vol. 18 ›› Issue (6): 2250-2257.doi: 10.1088/1674-1056/18/6/024
施德恒1, 张金平2, 孙金锋2, 朱遵略2
Shi De-Heng(施德恒)a)b)† , Zhang Jin-Ping(张金平)b), Sun Jin-Feng(孙金锋)a), and Zhu Zun-Lue(朱遵略)a)
摘要: Interaction potential of the SiD(X2П) radical is constructed by using the CCSD(T) theory in combination with the largest correlation-consistent quintuple basis set augmented with the diffuse functions in the valence range. Using the interaction potential, the spectroscopic parameters are accurately determined. The present D0, De, Re, ω e, α e and Be values are of 3.0956~eV, 3.1863~eV, 0.15223~nm, 1472.894~cm-1, 0.07799~cm-1 and 3.8717~cm-1, respectively, which are in excellent agreement with the measurements. A total of 26 vibrational states is predicted when J = 0 by solving the radial Schr?dinger equation of nuclear motion. The complete vibrational levels, classical turning points, initial rotation and centrifugal distortion constants when J=0 are reported for the first time, which are in good accord with the available experiments. The total and various partial-wave cross sections are calculated for the elastic collisions between Si and D atoms in their ground states at 1.0× 10-11--1.0× 10-3~a.u. when the two atoms approach each other along the SiD(X2П) potential energy curve. Four shape resonances are found in the total elastic cross sections, and their resonant energies are of 1.73× 10-5, 4.0× 10-5, 6.45× 10-5 and 5.5× 10-4~a.u., respectively. Each shape resonance in the total elastic cross sections is carefully investigated. 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 the higher partial waves, most of them are passed into oblivion by the strong s partial-wave elastic cross sections.
中图分类号: (Scattering of atoms and molecules)