The localized molecular orbital LMO model

The localized molecular orbital (LMO) model was first proposed by Nafie and Walnut (1977). In the context of this model the rotatory strength of a vibrational transition is evaluated by seperate contributions of each orbital and each nucleus. 

e denotes the charge of the electron, which has to be multiplied by (-2) for two-fold occupied orbitals. The full nuclear charge, Z is retained. is the vector of motion by the harmonic normal vibration Qp, the derivative of the position vector dR/dQp as in Eqs. 6.3-3 and 6.3-4. 

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