处理NaCs光解离问题的两种方案比较

利用含时波包动力学方法中的劈裂算符-傅里叶变换传播方案和切比雪夫多项式展开方案研究了Na Cs分子的光吸收截面,并对由这两种方案计算得出的结果进行了比较.结果表明劈裂算符-傅立叶变换传播方案能更好地展示光吸收截面的中间动力学信息,而在研究初始波包与光吸收截面的关系时,由切比雪夫多项式展开方案获得的结果则更直观.利用后一方案计算的从基态X1∑+不同振动态跃迁到激发态B1∑+上相应的光吸收截面的结果表明,初始波包对光吸收截面有一定的影响,所有振动态的吸收截面均表现出谐振行为,即每一个振动态吸收截面最小值的个数恰好等于基态振动态波函数节点的个数,这种节点映射行为与映射原理相符合.

Comparison of two schemes for investigating NaCs photo-dissociation

The present work investigates the photo-absorption cross section of NaCs by using the split operator-Fourier transform propagation scheme and the Chebyshev polynomial expansion scheme. The comparison of the two calculated results shows that the split operator scheme can better exhibit the intermediate results of the dynamics process, while the other scheme is hard to satisfy this requirement due to the long time step. In this paper the photo-absorption cross sections, corresponding to the wave packet of the different vibrational state in the ground state transited to the excited state, also are calculated. The results show that the initial wave packet has a certain impact on photo-absorption cross section. The photo-absorption cross section corresponding to the related vibrational state shows a resonant behavior, i.e. the number of the minimum of the cross section corresponding to the each vibrational state is exactly equal to the number of the node of the wave function in the ground vibrational state. This situation caused by the reflection of the wave packet is accordance with the well-known reflection principle.