Goj Anne, Loring Roger F
Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, NY 14853, USA.
J Chem Phys. 2006 May 21;124(19):194101. doi: 10.1063/1.2198203.
Multidimensional infrared spectroscopy probes coupled molecular vibrations in complex, condensed phase systems. Recent theoretical studies have focused on the analytic structure of the nonlinear response functions required to calculate experimental observables in a perturbative treatment of the radiation-matter interaction. Classical mechanical nonlinear response functions have been shown to exhibit unbounded growth for anharmonic, integrable systems, as a consequence of the nonlinearity of classical mechanics, a feature that is absent in a quantum mechanical treatment. We explore the analytic structure of the third-order vibrational response function for an exactly solvable quantum mechanical model that includes some of the important and theoretically challenging aspects of realistic models of condensed phase systems: anharmonicity, resonant coupling, fluctuations, and a well-defined classical mechanical limit.
多维红外光谱探针可探测复杂凝聚相系统中的耦合分子振动。最近的理论研究集中在辐射与物质相互作用的微扰处理中计算实验可观测量所需的非线性响应函数的解析结构。由于经典力学的非线性，对于非谐可积系统，经典力学非线性响应函数已被证明会呈现无界增长，这是量子力学处理中不存在的一个特征。我们探索了一个精确可解量子力学模型的三阶振动响应函数的解析结构，该模型包含了凝聚相系统现实模型的一些重要且在理论上具有挑战性的方面：非谐性、共振耦合、涨落以及明确的经典力学极限。
