Laboratory studies of Criegee radical reactions
Lead Research Organisation:
University of Southampton
Department Name: Sch of Chemistry
Abstract
Chemicals entering the atmosphere come from a number of sources, but in broad terms are either from human activity or from the biosphere (natural systems). What happens to these chemicals once in the atmosphere is very important of course. If they are toxic they can impact on the health of humans, animals and natural ecosystems. Therefore, it is vital that we understand how pollutants are removed by the atmosphere. One very important removal process involves the so called hydroxyl radical. This is an extremely reactive species that acts like a chemical detergent, destroying pollutants and cleaning up the atmosphere. It has emerged in recent investigations that an important source of the hydroxyl radical must be coming from Criegee radicals. However, these Criegee radicals have been impossible to measure until recently. Work carried out by us, using a facility in the USA, has allowed us to observe a Criegee radical for the first time. In this project we will develop a state-of-the-art experimental system that will allow us to investigate the chemistry of Criegee radicals and therefore to help us to understand how they affect the amount of hydroxyl radical is present in the atmosphere. Such work will not only improve our understanding of the urban environment but will also have implications for climate studies as well. Reactions of Criegee intermediates, over a wide range of pressure and temperature, are of importance in atmospheric chemistry. The proposed UV-PE apparatus will be the first of its kind and will enable us to carry out a range of experiments to study reactions of these radicals that, as far as we are aware, no one else in the world can do. To demonstrate how versatile the apparatus is we propose a carefully designed set of experiments to look at the source and fate of Criegee radicals in the troposphere. Quantum chemistry calculations of the reactions studied will provide detailed understanding of their mechanisms and the kinetic data will be incorporated into models describing the troposphere and compared with available measurements.
Organisations
People |
ORCID iD |
John Dyke (Principal Investigator) |
Publications
Copeland G
(2011)
A study of the alkene-ozone reactions, 2,3-dimethyl 2-butene + O3 and 2-methyl propene + O3, with photoelectron spectroscopy: measurement of product branching ratios and atmospheric implications
in Physical Chemistry Chemical Physics
Pinto RM
(2011)
Thermal decomposition of methyl 2-azidopropionate studied by UV photoelectron spectroscopy and matrix isolation IR spectroscopy: heterocyclic intermediate vs imine formation.
in The journal of physical chemistry. A
Ramasami, Ponnadurai; Gupta-Bhowon, Minu; Jhaumeer-Laulloo, Sabina; Li Kam Wah, Henri
(2011)
Chemistry for Sustainable Development
Mok DK
(2011)
Franck-Condon simulation, including anharmonicity, of the photodetachment spectrum of P2H(-): restricted-spin coupled-cluster single-double plus perturbative triple and unrestricted-spin coupled-cluster single-double plus perturbative triple -F12x potential energy functions of P2H and P2H(-).
in The Journal of chemical physics
Dyke J
(2012)
Chemistry for Sustainable Development
Pinto R
(2012)
Pyrolysis of 3-azidopropionitrile studied by UV photoelectron and matrix-isolation IR spectroscopies: Formation of ketenimine H2C C NH
in Journal of Molecular Structure
Rhyman L
(2012)
A study of the atmospherically important reactions between dimethyl selenide (DMSe) and molecular halogens (X2 = Cl2, Br2, and I2) with ab initio calculations.
in The journal of physical chemistry. A
Roscioni OM
(2012)
Development and testing of a compact basis set for use in effective core potential calculations on rhodium complexes.
in Journal of computational chemistry
Taatjes CA
(2012)
Direct measurement of Criegee intermediate (CH2OO) reactions with acetone, acetaldehyde, and hexafluoroacetone.
in Physical chemistry chemical physics : PCCP
Beccaceci S
(2012)
A study of the atmospherically important reactions of dimethylsulfide (DMS) with I2 and ICl using infrared matrix isolation spectroscopy and electronic structure calculations.
in Physical chemistry chemical physics : PCCP
Lee EP
(2012)
Spectroscopy of the simplest Criegee intermediate CH2OO: simulation of the first bands in its electronic and photoelectron spectra.
in Chemistry (Weinheim an der Bergstrasse, Germany)
Percival CJ
(2013)
Regional and global impacts of Criegee intermediates on atmospheric sulphuric acid concentrations and first steps of aerosol formation.
in Faraday discussions
Ng M
(2013)
Rate coefficients of the CF3CHFCF3 + H ? CF3CFCF3 + H2 reaction at different temperatures calculated by transition state theory with ab initio and DFT reaction paths.
in Journal of computational chemistry
Innocenti F
(2013)
Threshold photoelectron spectroscopy of vibrationally excited nitrogen
in Journal of Physics B: Atomic, Molecular and Optical Physics
Taatjes CA
(2013)
Direct measurements of conformer-dependent reactivity of the Criegee intermediate CH3CHOO.
in Science (New York, N.Y.)
Roscioni O
(2013)
Structural Characterization of Supported Rh I (CO) 2 /?-Al 2 O 3 Catalysts by Periodic DFT Calculations
in The Journal of Physical Chemistry C
Mok DK
(2013)
Simulated photodetachment spectra of AlH2(-).
in The Journal of chemical physics
Chow R
(2014)
Rate coefficients of the Cl + CH3C(O)OCH3 ? HCl + CH3C(O)OCH2 reaction at different temperatures calculated by transition-state theory with ab initio and density functional theory reaction paths.
in The journal of physical chemistry. A
Copeland G
(2014)
Determination of the photolysis rate coefficient of monochlorodimethyl sulfide (MClDMS) in the atmosphere and its implications for the enhancement of SO2 production from the DMS + Cl2 reaction.
in Environmental science & technology
Roeterdink W
(2014)
Hexapole transmission spectrum of formaldehyde oxide
in Chemical Physics Letters
Ng M
(2014)
Decomposition reactions of hexafluoropropylene oxide (HFPO): Rate coefficients calculated at different temperatures using ab initio and DFT reaction paths
in Journal of Fluorine Chemistry
Ng M
(2015)
A theoretical study of the mechanism of the atmospherically relevant reaction of chlorine atoms with methyl nitrate, and calculation of the reaction rate coefficients at temperatures relevant to the troposphere.
in Physical chemistry chemical physics : PCCP
Shallcross DE
(2015)
Reaction between CH3O2 and BrO radicals: a new source of upper troposphere lower stratosphere hydroxyl radicals.
in The journal of physical chemistry. A
Khan M
(2016)
A modelling study of the atmospheric chemistry of DMS using the global model, STOCHEM-CRI
in Atmospheric Environment
Chow R
(2016)
A theoretical study of the atmospherically important radical-radical reaction BrO + HO2; the product channel O2(a1?g) + HOBr is formed with the highest rate.
in Physical chemistry chemical physics : PCCP
Schio L
(2016)
A Study of H2O2 with Threshold Photoelectron Spectroscopy (TPES) and Electronic Structure Calculations: Redetermination of the First Adiabatic Ionization Energy (AIE).
in The journal of physical chemistry. A
Chhantyal-Pun R
(2017)
Direct Measurements of Unimolecular and Bimolecular Reaction Kinetics of the Criegee Intermediate (CH3)2COO.
in The journal of physical chemistry. A
Description | Understanding the role of Criegee intermediates in the oxidation chemistry of the atmosphere has been improved |
Exploitation Route | The results can be used by atmospheric modellers to improve predictions of atmospheric chemistry and climate. |
Sectors | Environment |
Description | The results obtained have been used to contribute to an understanding of the oxidising capacity of the atmosphere and climate change. Prof Dyke has spent 5 x 2-week (and 3x2 day) visits to Prof Percival's laboratory in Manchester to develop a Photoelectron Spectrometer to study Criegee intermediates and their reactions. This spectrometer is now nearing completion and the postdoctoral fellow (Dr Bacak) will be taking first data in the next 3 months. |
First Year Of Impact | 2003 |
Sector | Environment |
Impact Types | Policy & public services |
Description | Atmospheric Chemistry, Climate Change and Criegee intermediates |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | Yes |
Geographic Reach | Local |
Primary Audience | Schools |
Results and Impact | A general talk to the Sixth Form at Barton Peveril School Eastleigh, Hampshire under the auspices of the Royal Society of Chemistry(RSC). A lecture of atmospheric chemistry to a sixth form school audience. |
Year(s) Of Engagement Activity | 2013 |