Measurements of Rate Coefficients for Reactions of OH with Ethanol and Propan-2-ol at Very Low Temperatures

The low temperature kinetics of the reactions of OH with ethanol and propan-2-ol have been studied using a pulsed Laval nozzle apparatus coupled with pulsed laser photolysis–laser-induced fluorescence (PLP-LIF) spectroscopy. The rate coefficients for both reactions have been found to increase signif...

Full description

Saved in:
Bibliographic Details
Published in:The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory Molecules, spectroscopy, kinetics, environment, & general theory, 2015-07, Vol.119 (28), p.7130-7137
Main Authors: Caravan, Rebecca L, Shannon, Robin J, Lewis, Thomas, Blitz, Mark A, Heard, Dwayne E
Format: Article
Language:English
Subjects:
Ethanol - chemistry
Gases - chemistry
Hydroxyl Radical - chemistry
Kinetics
Least-Squares Analysis
Linear Models
Nonlinear Dynamics
Photolysis
Pressure
Propanols - chemistry
Spectrometry, Fluorescence
Temperature
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The low temperature kinetics of the reactions of OH with ethanol and propan-2-ol have been studied using a pulsed Laval nozzle apparatus coupled with pulsed laser photolysis–laser-induced fluorescence (PLP-LIF) spectroscopy. The rate coefficients for both reactions have been found to increase significantly as the temperature is lowered, by approximately a factor of 18 between 293 and 54 K for ethanol, and by ∼10 between 298 and 88 K for OH + propan-2-ol. The pressure dependence of the rate coefficients provides evidence for two reaction channels: a zero pressure bimolecular abstraction channel leading to products and collisional stabilization of a weakly bound OH–alcohol complex. The presence of the abstraction channel at low temperatures is rationalized by a quantum mechanical tunneling mechanism, most likely through the barrier to hydrogen abstraction from the OH moiety on the alcohol.
ISSN:1089-5639
1520-5215
DOI:10.1021/jp505790m