This chapter offers an introductory theoretical treatment of the vibration aspects of the hydrogen bond. A hydrogen bonded system is characterized by the interaction of intra- and intermolecular forces. As a result a proper description of the corresponding vibrations can only be obtained from a quantummechanical treatment. This is illustrated in a pictorial way for the case of the stretching vibrations in a linear A-H-B system. Such a system exhibits a double-well potential, which deviates considerably from the classical two-dimensional harmonic oscillator. Solutions of the wave equation for nuclear motion in this potential are discussed, with special attention to the splitting effect of the double well and the coupling of the vs and νσ vibrations.
KeywordsPrincipal Curvature Nuclear Motion Nuclear Position Kinetic Energy Operator Tunneling Transition
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