Polyatomic molecules nonlinear optics

In this chapter we review some of the developments that have been made over the past fifteen years with regard to the calculation of vibrational contributions to linear and nonlinear (NLO) optical properties. Despite a number of advances it is important to recognize that more are needed since there is still no fully satisfactory general treatment for either resonant or non-resonant NLO processes in polyatomic molecules. Two major intertwining approaches to practical computations that include electrical and mechanical anharmonicity have emerged. The older approach is from the viewpoint of ordinary sum-over-states perturbation theory and it is presented in Section 1. The other approach, discussed in Section 2, is from what may be called the nuclear relaxation/curvature point of view. Even though there is 101... 

VI. Nonlinear Optics of Polyatomic Harmonic Molecules in Condensed Phases— Eigenstate-Free Spectroscopy... 

We consider a nonlinear optical medium, consisting of polyatomic molecules interacting with a classical external electromagnetic field by a dipolar interaction. The total Hamiltonian of the system is... 

VI. NONLINEAR OPTICS OF POLYATOMIC HARMONIC MOLECULES IN CONDENSED PHASES— EIGENSTATE-FREE ... 

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