Next, the spin-orbit coupling force is introduced by a certain approximate method, and an energy spectrum comparable with experiment is obtained.
第二步用一种近似办法加进了自旋轨道耦合力，得到了可以和实验进行比较的能谱。
2
This model is solved by applying the direct perturbation method. The time evolution of spectrum and the first order approximate wave function for the system are presented.
利用直接微扰法，给出了该系统的一级近似波函数及能谱随时间的演化规律。
3
Furthermore, an approximate algorithm is pro-posed to compute the kinetic spectrum of each species, thus making the method effective as well for reactions with fractional orders.