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On the Use of Quantum Thermal Bath in Unimolecular Fragmentation Simulations

revised on 02.09.2019, 14:39 and posted on 04.09.2019, 17:15 by Riccardo Spezia, Hichem Dammak

In the present work we have investigated the possibility of using the Quantum Thermal Bath (QTB) method in molecular simulations of unimolecular dissociation processes. Notably, QTB is aimed in introducing quantum nuclear effects with a com- putational time which is basically the same as in newtonian simulations. At this end we have considered the model fragmentation of CH4 for which an analytical function is present in the literature. Moreover, based on the same model a microcanonical algorithm which monitor zero-point energy of products, and eventually modifies tra- jectories, was recently proposed. We have thus compared classical and quantum rate constant with these different models. QTB seems to correctly reproduce some quantum features, in particular the difference between classical and quantum activation energies, making it a promising method to study unimolecular fragmentation of much complex systems with molecular simulations. The role of QTB thermostat on rotational degrees of freedom is also analyzed and discussed.


ANR DynBioReact ANR-14-CE06)0029-01


Email Address of Submitting Author


Sorbonne Université, CNRS Laboratoire Chimie Théorique UMR 7616



ORCID For Submitting Author


Declaration of Conflict of Interest

No conflict of interest

Version Notes

12th July version


Read the published paper

in The Journal of Physical Chemistry A

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