Anharmonic quantum contribution to vibrational dephasing

Abstract

The evaluation of vibrational dephasing rate of a cubic oscillator using quantum Langevin equation and its corresponding Hamiltonian within a c-number formalism was discussed. The calculation of the quantum correction due to the nonlinearity of the system potential was also discussed. It was found that leading order quantum correction due to anharmonicity of the potential has a significant contribution to the frequency shift and the vibrational dephasing rate. It was also found that the quantum correction had a significant role in triatomic and polyatomic molecules.