Communication: Mechanochemical fluctuation theorem and thermodynamics of self-phoretic motors
Communication: Mechanochemical fluctuation theorem and thermodynamics of self-phoretic motors
Publication Type:
Journal ArticleSource:
Journal of Chemical Physics, American Institute of Physics Inc., Volume 147, Number 21 (2017)URL:
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85037057678&doi=10.1063%2f1.5008562&partnerID=40&md5=5152a1c47454312af6cb4f8a8f3acf23Keywords:
Catalysis, Catalytic reactions, Chemical fluctuations, Concentration fields, Differential equations, Fluctuation theorems, Fluid velocity field, Joint probability, Mechanochemical couplings, Microscopic reversibility, Molecular dynamics, Propulsion, Reaction kinetics, Surface reactions, Thermodynamics, VelocityAbstract:
<p>Microscopic dynamical aspects of the propulsion of nanomotors by self-phoretic mechanisms are considered. Propulsion by self-diffusiophoresis relies on the mechanochemical coupling between the fluid velocity field and the concentration fields induced by asymmetric catalytic reactions on the motor surface. The consistency between the thermodynamics of this coupling and the microscopic reversibility of the underlying molecular dynamics is investigated. For this purpose, a mechanochemical fluctuation theorem for the joint probability to find the motor at position r after n reactive events have occurred during the time interval t is derived, starting from coupled Langevin equations for the translational, rotational, and chemical fluctuations of self-phoretic motors. An important result that follows from this analysis is the identification of an effect that is reciprocal to self-propulsion by diffusiophoresis, which leads to a dependence of the reaction rate on the value of an externally applied force. © 2017 Author(s).</p>
