Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

SN2 Reaction: Kinetics

S_N2 Reaction: Kinetics

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...

Multi-Step Reactions

Multi-Step Reactions

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. Each of the steps in a reaction mechanism is called an elementary reaction. These...

SN1 Reaction: Kinetics

S_N1 Reaction: Kinetics

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...

Dynamic Equilibrium

Dynamic Equilibrium

A reversible chemical reaction represents a chemical process that proceeds in both forward (left to right) and reverse (right to left) directions. When the rates of the forward and reverse reactions are equal, the concentrations of the reactant and product species remain constant over time and the system is at equilibrium. A special double arrow is used to emphasize the reversible nature of the reaction. The relative concentrations of reactants and products in equilibrium systems vary greatly;...

SN2 Reaction: Transition State

S_N2 Reaction: Transition State

An SN2 reaction of an alkyl halide is a single-step process in which bond formation between the nucleophile and the substrate and bond breaking between the substrate and the halide occurs simultaneously through a transition state without forming an intermediate.
When the nucleophile approaches the electrophilic carbon with its lone pairs, the halide acts as a leaving group and moves away with the electron-pair bonded to the carbon. Dotted partial bonds represent the bonds being formed or broken...

Reaction Mechanisms

Reaction Mechanisms

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:

You might also read

Related Articles

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

Sort by

Same author

Laser-Controlled Ion-Molecule Reaction Kinetics: Be<sup>+</sup> + H<sub>2</sub>O at Variable Reaction Temperatures.

The journal of physical chemistry letters·2025

Same author

Construction of polymethine chain-modified pentamethylene cyanine dyes for G-quadruplex imaging in live cells.

Chemical communications (Cambridge, England)·2025

Same author

Effect of SiO<sup>+</sup> Rotational Excitation on Dynamics of SiO<sup>+</sup> + H<sub>2</sub> → SiOH<sup>+</sup> + H Reaction.

The journal of physical chemistry. A·2025

Same author

Visual Quantitation of Dopamine-Inspired Fluorescent Adhesion with Orthogonal Phenanthrenequinone Photochemistry.

ACS macro letters·2024

Same author

Non-IRC Mechanism of Bimolecular Reactions with Submerged Barriers: A Case Study of Si<sup>+</sup> + H<sub>2</sub>O Reaction.

The journal of physical chemistry. A·2024

Same author

Isolation of Fluorescent 2π-Aromatic 1,3-Disiladiboretenes.

Journal of the American Chemical Society·2023

Search research articles

Related Experiment Video

Updated: Oct 21, 2025

Ammonia Synthesis at Low Pressure

Ammonia Synthesis at Low Pressure

Published on: August 23, 2017

Mode-specific dynamics in multichannel reaction NH⁺ + H₂.

Weiliang Shi¹, Kun Wang¹, Ping Zhang¹

¹Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, 710127, P. R. China. yule@nwu.edu.cn.

Physical Chemistry Chemical Physics : PCCP

|September 7, 2021

Summary

Investigating the NH+ + H2 reaction, this study reveals how vibrational and rotational excitation influences different reaction pathways. Rotational excitation of NH+ significantly boosts hydrogen transfer reactions, while vibrational excitation inhibits them.

More Related Videos

Analyzing Protein Dynamics Using Hydrogen Exchange Mass Spectrometry

Analyzing Protein Dynamics Using Hydrogen Exchange Mass Spectrometry

Published on: November 29, 2013

Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid

Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid

Published on: November 15, 2017

Related Experiment Videos

Last Updated: Oct 21, 2025

Ammonia Synthesis at Low Pressure

Ammonia Synthesis at Low Pressure

Published on: August 23, 2017

Analyzing Protein Dynamics Using Hydrogen Exchange Mass Spectrometry

Analyzing Protein Dynamics Using Hydrogen Exchange Mass Spectrometry

Published on: November 29, 2013

Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid

Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid

Published on: November 15, 2017

Area of Science:

Chemical Kinetics
Molecular Dynamics
Quantum Chemistry

Background:

Understanding ion-molecule reactions is crucial in astrochemistry and plasma physics.
The NH+ + H2 system is a key model for studying complex reaction dynamics.

Purpose of the Study:

To investigate the vibrational- and rotational-mode specificity of the multichannel NH+ + H2 reaction.
To analyze the influence of reactant excitation on different reaction pathways and mechanisms.

Main Methods:

Utilized an initial state selected quasi-classical trajectory method on an ab initio-based global potential energy surface.
Employed isometric feature mapping and k-means clustering for trajectory analysis.

Main Results:

Vibrational and rotational excitation of NH+ promotes bond-breaking reactions (R1 and R4) but reduces proton-transfer (R2) at low energies.
Rotational excitation of NH+ significantly enhances the hydrogen-transfer reaction (R3), while vibrational excitation inhibits it.
H2 reactant motion enhances reactivity but does not alter the mechanism of R3.

Conclusions:

The study elucidates the mode-specific effects on the NH+ + H2 reaction dynamics.
The combination of isometric feature mapping and k-means clustering is effective for reaction dynamics studies.