TY - JOUR
T1 - Nonstatistical reaction dynamics
AU - Jayee, Bhumika
AU - Hase, William L.
N1 - Funding Information:
The Hase research group is supported by the Welch Foundation under grant D-0005 and the Air ForceOffice of Scientific Research under AFOSR awards FA9550-16-1-0133,FA9550-17-1-0107, and FA9550-17-1-0119.
Publisher Copyright:
Copyright © 2020 by Annual Reviews. All rights reserved.
PY - 2020/4/20
Y1 - 2020/4/20
N2 - Nonstatistical dynamics is important for many chemical reactions. The Rice-Ramsperger-Kassel-Marcus (RRKM) theory of unimolecular kinetics assumes a reactant molecule maintains a statistical microcanonical ensemble of vibrational states during its dissociation so that its unimolecular dynamics are time independent. Such dynamics results when the reactant's atomic motion is chaotic or irregular. Intrinsic non-RRKM dynamics occurs when part of the reactant's phase space consists of quasiperiodic/regular motion and a bottleneck exists, so that the unimolecular rate constant is time dependent. Nonrandom excitation of a molecule may result in short-time apparent non-RRKM dynamics. For rotational activation, the 2J + 1 K levels for a particular J may be highly mixed, making K an active degree of freedom, or K may be a good quantum number and an adiabatic degree of freedom. Nonstatistical dynamics is often important for bimolecular reactions and their intermediates and for product-energy partitioning of bimolecular and unimolecular reactions. Post-transition state dynamics is often highly complex and nonstatistical.
AB - Nonstatistical dynamics is important for many chemical reactions. The Rice-Ramsperger-Kassel-Marcus (RRKM) theory of unimolecular kinetics assumes a reactant molecule maintains a statistical microcanonical ensemble of vibrational states during its dissociation so that its unimolecular dynamics are time independent. Such dynamics results when the reactant's atomic motion is chaotic or irregular. Intrinsic non-RRKM dynamics occurs when part of the reactant's phase space consists of quasiperiodic/regular motion and a bottleneck exists, so that the unimolecular rate constant is time dependent. Nonrandom excitation of a molecule may result in short-time apparent non-RRKM dynamics. For rotational activation, the 2J + 1 K levels for a particular J may be highly mixed, making K an active degree of freedom, or K may be a good quantum number and an adiabatic degree of freedom. Nonstatistical dynamics is often important for bimolecular reactions and their intermediates and for product-energy partitioning of bimolecular and unimolecular reactions. Post-transition state dynamics is often highly complex and nonstatistical.
KW - SN2 reaction dynamics
KW - active rotation
KW - adiabatic rotation
KW - bimolecular reactions
KW - non-RRKM unimolecular dynamics
KW - nonintrinsic reaction coordinate dynamics
KW - nonstatistical reaction dynamics
KW - phase space dynamics
KW - post-transition state dynamics
KW - product energy partitioning
KW - reaction intermediates
KW - rotational/vibrational coupling
UR - http://www.scopus.com/inward/record.url?scp=85084181147&partnerID=8YFLogxK
U2 - 10.1146/annurev-physchem-112519-110208
DO - 10.1146/annurev-physchem-112519-110208
M3 - Review article
AN - SCOPUS:85084181147
VL - 71
SP - 289
EP - 313
JO - Annual Review of Physical Chemistry
JF - Annual Review of Physical Chemistry
SN - 0066-426X
ER -