Polley Kritanjan, Loring Roger F
Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, USA.
J Chem Phys. 2019 Apr 28;150(16):164114. doi: 10.1063/1.5093911.
We present a semiclassical procedure for calculating nonlinear optical spectra from a quantum Hamiltonian with discrete electronic states. The purely electronic Hamiltonian for N states is first mapped to the associated Meyer-Miller Hamiltonian for N quantum harmonic oscillators. The classical limit is then taken, and classical nuclear degrees of freedom are introduced. Spectra are calculated by propagating the classical analogs of transition dipole operators subject to semiclassical quantization conditions on action variables. This method generalizes the optimized-mean-trajectory approach, originally developed for nonlinear vibrational spectroscopy and subsequently extended to vibronic spectroscopy, to models with multiple interacting electronic states. Calculations for two electronic excited states with displaced harmonic nuclear potentials illustrate the implementation of this approach.
我们提出了一种半经典方法，用于从具有离散电子态的量子哈密顿量计算非线性光学光谱。首先将N个态的纯电子哈密顿量映射到N个量子谐振子的相关迈耶 - 米勒哈密顿量。然后取经典极限，并引入经典核自由度。通过传播跃迁偶极矩算符的经典类似物，并根据作用变量上的半经典量子化条件来计算光谱。该方法将最初为非线性振动光谱开发并随后扩展到振转光谱的优化平均轨迹方法推广到具有多个相互作用电子态的模型。对具有位移谐波核势的两个电子激发态的计算说明了该方法的实现。
