TY - JOUR
T1 - Stochastic Kinetics and Equilibrium of Nanoconfined Reactions
AU - Khodorkovsky, Yuri
AU - Rubinovich, Leonid
AU - Polak, Micha
N1 - Funding Information:
L.R. acknowledges the Israel Ministry of Immigrant Absorption for continued financial support under the KAMEA program.
Publisher Copyright:
© 2019 American Chemical Society.
PY - 2019/10/10
Y1 - 2019/10/10
N2 - This theoretical/computational work aims at elucidating the stochastic kinetics and eventual equilibrium state of elementary reactions involving a small number of spatially confined molecules. The modeling is based on chemical master equation solved using the Gillespie algorithm, which is a variant of dynamic Monte Carlo simulations. The behavior of the system reaching equilibrium conditions agrees with statistical mechanics predictions published by us previously (termed "nanoconfinement entropic effect on chemical equilibrium", NCECE). It is shown that both effects can be accounted for by thermal fluctuations in the number of product molecules in the small closed system, thus providing a distinct physicochemical insight into the processes. Compared to the deterministic kinetics characteristic of macroscopic systems, and depending on the reaction thermicity, acceleration or deceleration of the stochastic kinetics is predicted for addition and exchange bimolecular reactions. Moreover, it is found that the stochastic kinetic effect can temporarily exceed the NCECE in magnitude of the extra product formation. Quite remarkably, the effect is amplified in the case of a pair of nanoconfined consecutive exchange reactions, and a rule of combining their equilibrium constants is proposed.
AB - This theoretical/computational work aims at elucidating the stochastic kinetics and eventual equilibrium state of elementary reactions involving a small number of spatially confined molecules. The modeling is based on chemical master equation solved using the Gillespie algorithm, which is a variant of dynamic Monte Carlo simulations. The behavior of the system reaching equilibrium conditions agrees with statistical mechanics predictions published by us previously (termed "nanoconfinement entropic effect on chemical equilibrium", NCECE). It is shown that both effects can be accounted for by thermal fluctuations in the number of product molecules in the small closed system, thus providing a distinct physicochemical insight into the processes. Compared to the deterministic kinetics characteristic of macroscopic systems, and depending on the reaction thermicity, acceleration or deceleration of the stochastic kinetics is predicted for addition and exchange bimolecular reactions. Moreover, it is found that the stochastic kinetic effect can temporarily exceed the NCECE in magnitude of the extra product formation. Quite remarkably, the effect is amplified in the case of a pair of nanoconfined consecutive exchange reactions, and a rule of combining their equilibrium constants is proposed.
UR - http://www.scopus.com/inward/record.url?scp=85073122386&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcc.9b07267
DO - 10.1021/acs.jpcc.9b07267
M3 - Article
AN - SCOPUS:85073122386
SN - 1932-7447
VL - 123
SP - 24949
EP - 24956
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
IS - 40
ER -