Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Measuring Reaction Rates03:09

Measuring Reaction Rates

28.4K
Polarimetry finds application in chemical kinetics to measure the concentration and reaction kinetics of optically active substances during a chemical reaction. Optically active substances have the capability of rotating the plane of polarization of linearly polarized light passing through them—a feature called optical rotation. Optical activity is attributed to the molecular structure of substances. Normal monochromatic light is unpolarized and possesses oscillations of the electrical...
28.4K
Reaction Rate02:53

Reaction Rate

61.5K
The rate of reaction is the change in the amount of a reactant or product per unit time. Reaction rates are therefore determined by measuring the time dependence of some property that can be related to reactant or product amounts. Rates of reactions that consume or produce gaseous substances, for example, are conveniently determined by measuring changes in volume or pressure.
The mathematical representation of the change in the concentration of reactants and products, over time, is the rate...
61.5K
SN1 Reaction: Kinetics02:05

SN1 Reaction: Kinetics

9.4K
In an SN2 reaction, the reaction rate depends on both the type of nucleophile and the substrate. A hindered tertiary alkyl halide is practically inert to the SN2 mechanism despite using a strong nucleophile.
However, Sir Christopher Ingold and Edward D. Hughes, who studied the kinetics of various nucleophilic substitution reactions, noticed that a tertiary alkyl halide does undergo a nucleophilic substitution reaction in the presence of a weak nucleophile. While studying the substitution...
9.4K
Reaction Mechanisms03:06

Reaction Mechanisms

30.3K
Chemical reactions often occur in a stepwise fashion, involving two or more distinct reactions taking place in a sequence. A balanced equation indicates the reacting species and the product species, but it reveals no details about how the reaction occurs at the molecular level. The reaction mechanism (or reaction path) provides details regarding the precise, step-by-step process by which a reaction occurs.
For instance, the decomposition of ozone appears to follow a mechanism with two steps:
30.3K
Predicting Reaction Outcomes02:24

Predicting Reaction Outcomes

9.8K
Kinetics describes the rate and path by which a reaction occurs. In contrast, thermodynamics deals with state functions and describes the properties, behavior, and components of a system. It is not concerned with the path taken by the process and cannot address the rate at which a reaction occurs. Although it does provide information about what can happen during a reaction process, it does not describe the detailed steps of what appears on an atomic or a molecular level. On the other hand,...
9.8K
SN2 Reaction: Kinetics02:14

SN2 Reaction: Kinetics

10.0K
Kinetic Studies and Significance
In a chemical reaction, a relationship exists between the concentration of reactants and the rate at which the reaction proceeds. The study to measure this relationship is known as the kinetics of a chemical reaction. Kinetic studies are used to deduce the rate law of a chemical reaction, which provides information about the species involved during the transition state of the rate-determining step. Thus, kinetic studies help to derive the mechanism of a...
10.0K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

COLUMBUS─An Efficient and General Program Package for Ground and Excited State Computations Including Spin-Orbit Couplings and Dynamics.

The journal of physical chemistry. A·2025
Same author

RNA Metabolism and the Role of Small RNAs in Regulating Multiple Aspects of RNA Metabolism.

Non-coding RNA·2025
Same author

Polyradical character assessment using multireference calculations and comparison with density-functional derived fractional occupation number weighted density analysis.

Physical chemistry chemical physics : PCCP·2023
Same author

High-Level Multireference Investigations on the Electronic States in Single-Vacancy (SV) Graphene Defects Using a Pyrene-SV Model.

The journal of physical chemistry. A·2023
Same author

Chemical dynamics simulations of energy transfer in CH<sub>4</sub> and N<sub>2</sub> collisions.

RSC advances·2022
Same author

Mechanism and kinetics for the reaction of methyl peroxy radical with O<sub>2</sub>.

Physical chemistry chemical physics : PCCP·2021

Related Experiment Video

Updated: Dec 23, 2025

Rapid in-silico Battery Electrolyte Electrochemical Reaction Generation using 3T-VASP Multi-Scale Energy Minimization
05:37

Rapid in-silico Battery Electrolyte Electrochemical Reaction Generation using 3T-VASP Multi-Scale Energy Minimization

Published on: August 22, 2025

520

Nonstatistical Reaction Dynamics.

Bhumika Jayee1, William L Hase1

  • 1Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, USA;

Annual Review of Physical Chemistry
|April 22, 2020
PubMed
Summary
This summary is machine-generated.

Nonstatistical dynamics deviate from standard Rice-Ramsperger-Kassel-Marcus (RRKM) theory, impacting chemical reaction rates. This occurs when molecular motion is not fully chaotic, leading to time-dependent kinetics.

Keywords:
SN2 reaction dynamicsactive rotationadiabatic rotationbimolecular reactionsnon-RRKM unimolecular dynamicsnonintrinsic reaction coordinate dynamicsnonstatistical reaction dynamicsphase space dynamicspost–transition state dynamicsproduct energy partitioningreaction intermediatesrotational/vibrational coupling

More Related Videos

Modeling Fast-scan Cyclic Voltammetry Data from Electrically Stimulated Dopamine Neurotransmission Data Using QNsim1.0
07:41

Modeling Fast-scan Cyclic Voltammetry Data from Electrically Stimulated Dopamine Neurotransmission Data Using QNsim1.0

Published on: June 5, 2017

10.2K
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
11:03

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids

Published on: December 4, 2017

8.9K

Related Experiment Videos

Last Updated: Dec 23, 2025

Rapid in-silico Battery Electrolyte Electrochemical Reaction Generation using 3T-VASP Multi-Scale Energy Minimization
05:37

Rapid in-silico Battery Electrolyte Electrochemical Reaction Generation using 3T-VASP Multi-Scale Energy Minimization

Published on: August 22, 2025

520
Modeling Fast-scan Cyclic Voltammetry Data from Electrically Stimulated Dopamine Neurotransmission Data Using QNsim1.0
07:41

Modeling Fast-scan Cyclic Voltammetry Data from Electrically Stimulated Dopamine Neurotransmission Data Using QNsim1.0

Published on: June 5, 2017

10.2K
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
11:03

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids

Published on: December 4, 2017

8.9K

Area of Science:

  • Chemical Kinetics
  • Molecular Dynamics

Background:

  • The Rice-Ramsperger-Kassel-Marcus (RRKM) theory assumes statistical molecular dynamics for unimolecular reactions.
  • This assumption holds when atomic motion is chaotic, leading to time-independent rate constants.

Purpose of the Study:

  • To explore scenarios where non-RRKM dynamics are significant.
  • To understand the conditions leading to time-dependent unimolecular rate constants.

Main Methods:

  • Analysis of molecular phase space, distinguishing between chaotic and quasiperiodic/regular motion.
  • Consideration of nonrandom molecular excitation and rotational activation effects on dynamics.

Main Results:

  • Intrinsic non-RRKM dynamics arise from bottlenecks in quasiperiodic/regular regions of phase space.
  • Nonrandom excitation can cause short-time apparent non-RRKM behavior.
  • The role of the quantum number K in rotational activation influences dynamics.

Conclusions:

  • Nonstatistical dynamics are crucial for understanding complex chemical reactions, including bimolecular reactions and product energy partitioning.
  • Post-transition state dynamics are frequently nonstatistical and complex.