Radiation Chemical Kinetics in Condensed Media and Heterogeneous Mixed Phase Systems

Prof. Simon M. Pimblott

St. Peter
's College, University of Oxford
B.A. ('85), M.A. ('88), D.Phil. ('88)

Tel. +44 (0) 161 275 1325
Fax. +44 (0) 161 275 4734
e-mail: Simon.Pimblott@manchester.ac.uk

Group research page

Scientific Interests

Radiation chemical kinetics : elucidation of the ultra-fast radiation-induced chemistry of homogeneous and heterogeneous systems.

Effects of track structure : stochastic simulation of radiation tracks, and understanding of the chemical consequences of track structure.

Low energy electrons in condensed media : modeling of the attenuation, thermalization and ultra-fast chemistry of low energy electrons in condensed media.

Kinetic of nonhomogeneous systems : development of models for diffusion-limited reaction in structurally complex systems.

Recent Accomplishments

Existence of a scavengable precursor to molecular hydrogen : stochastic calculations suggested, and experiments demonstrated, a short-lived precursor to molecular hydrogen in water radiolysis. Scavengers for the precursors to the hydrated electron react with this species with the same relative rates, i.e. SeO42– > NO3 > NO2 > CH3COCH3 > H2O2 > Cd2+ > Cu2+.

Track structure effects in radiation chemistry : simulations show significant effects of particle energy in the electron, X-ray and synchrotron radiolysis of the Fricke dosimeter and of solutions of OH radical scavengers in water that can be traced to the track structure of the ionizing particle.

Energy loss properties of non-relativistic electrons in polymers : at low energy, the energy loss properties of electrons in polymers are very different from those of simple solid hydrocarbons with the same base units, however, at high energy, polymers have the same energy loss properties as the simple solid hydrocarbons.

Radiation chemistry of in high-LET muon track ends : the observed muon and muonium asymmetry in hydrocarbons is explained in terms of muonium formation within the radiation track and does not necessarily require a prompt component.

Selected Publications

P. Rajesh, J.A. LaVerne & S.M. Pimblott, High Dose Radiolysis of Aqueous Solutions of Chloromethanes: Importance in the Storage of Radioactive Organic Wastes, J. Nucl. Mater., 2007, 361, 10-7.

E.J. Edwards, P.H. Wilson, L. Anderson, D.M. Bartels, S.M. Pimblott, B. Schmidt, D. Ludwig, J. Prazak & T. Setter, University of Wisconsin Supercritical Water loop Radiation Deposition Calibration, Trans. Am. Nucl. Soc., 2006, 94, 533-4.

K. Enomoto, J.A. LaVerne, & S.M. Pimblott, Products of the Triplet Excited State Produced in the Radiolysis of Liquid Benzene, J. Phys. Chem. A, 2006, 110, 4124-30.

S.M. Pimblott, B.H. Milosavljevic & J.A. LaVerne, Radiolysis of Aqueous Solutions of 1,1- and 1,2-Dichloroethane, J. Phys. Chem. A, 2005, 109, 10294-301.

J.A. LaVerne, I. Štefanić & S.M. Pimblott, Hydrated Electron Yields in the Heavy Ion Radiolysis of Water, J. Phys. Chem. A, 2005, 109, 9393-401.

B.H. Milosavljevic, J.A. LaVerne & S.M. Pimblott, Rate Coefficient Measurements of Hydrated Electrons and Hydroxyl Radicals with Chlorinated Ethanes in Aqueous Solutions, J. Phys. Chem. A, 2005, 109, 7751-6.