Inertia-corrected budó treatment of dielectric relaxation in polar molecules: Application to the fir spectrum of acetonttrile and hexanone-2

The theory of dielectric relaxation of an assembly of molecules with neareit-neighbour dipole-dipole coupling, originally developed by Budó, is extended to include inertial effects. This yields an orientational correlation function that gives rise to Debye-type absorption in the microwave region and resonance absorption in the FIR region. The results are formally similar to the itinerant-oscillator model when the outer cage in that model carries a dipole moment. The results compare favourably with experimental observations on acetonitrile and hexanone-2.