Abstract
We study the dynamics of a Brownian particle in Morse potential under thermal fluctuations, modelled by Gaussian white noise whose amplitude depends on absolute temperature. Dynamics of such a particle is investigated by numerically integrating the corresponding Langevin equation. From the mean first passage time (escape time), we study the dependence of Kramer’s rate on temperature and viscosity of the medium. An approximate analytical expression for the rate constant is found by solving differential equation for the mean first passage time. The expression shows a temperature dependent pre-factor for the Arrhenius equation. Our numerical simulations are in agreement with the analytical approximations.
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Vipin, P., Sankaranarayanan, R. Exit dynamics from Morse potential under thermal fluctuations. Pramana - J Phys 97, 43 (2023). https://doi.org/10.1007/s12043-023-02527-y
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DOI: https://doi.org/10.1007/s12043-023-02527-y