An Exact Propagator for Solving the Triatomic Reactive Schrodinger Equation  

一种精确求解三原子反应散射的传播子

作　　者：李学明 孙志刚[1] 

机构地区：[1]中国科学院大连化学物理研究所分子反应动力学国家重点实验室和理论与计算化学中心,大连116023 [2]中国科学院大学,北京100049

出　　处：《Chinese Journal of Chemical Physics》2017年第6期761-770,I0003,共11页化学物理学报（英文）

摘　　要：The exact short time propagator, in a form similar to the Crank-Nicholson method but in the spirit of spectrally transformed Hamiltonian, was proposed to solve the triatomic reactive time-dependent schrodinger equation. This new propagator is exact and unconditionally convergent for calculating reactive scattering processes with large time step sizes. In order to improve the computational efficiency, the spectral difference method was applied. This resulted the Hamiltonian with elements confined in a narrow diagonal band. In contrast to our previous theoretical work, the discrete variable representation was applied and resulted in full Hamiltonian matrix. As examples, the collision energy-dependent probability of the triatomic H＋H2 and O＋O2 reaction are calculated. The numerical results demonstrate that this new propagator is numerically accurate and capable of propagating the wave packet with large time steps. However, the efficiency and accuracy of this new propagator strongly depend on the mathematical method for solving the involved linear equations and the choice of preconditioner.

关 键 词：Time-dependent wavepacket method Spectral difference Spectrally transformed Hamiltonian Exact short time propagator Reactive scattering 

分 类 号：O[理学]