Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235163
Title: Halogen 6* radicals : an ESR study
Author: Rowland, Ian J.
ISNI:       0000 0001 3538 7047
Awarding Body: University of Leicester
Current Institution: University of Leicester
Date of Award: 1988
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Abstract:
The main objective of the study was to characterise, by electron spin resonance (ESR) spectroscopy, novel halogen containing a* radicals. These species are formed by ?-irradiation in a variety of halogen containing systems at liquid nitrogen temperatures. In Chapter One, a brief description of the first halogen a* radical to be identified, the Vx centre in potassium chloride (C12.-), is given in order to illustrate the general magnetic properties of the species. The dependence of these properties on the host matrix is also described. Accepted radiation damage mechanisms are presented with particular reference to dihalogen a* radicals. Some theoretical aspects of the ESR experiment is discussed in Chapter Two which explains briefly some of the phenomena encountered in the study. Sample preparation and analysis are also mentioned. Chapter Three describes the characteristics of the simplest halogen containing a* radical: the hydrogen halide radical anion. Hydrogen fluoride, hydrogen chloride, hydrogen bromide and hydrogen iodide radical anions isolated in a variety of host matrices are reported. The large matrix dependence of their magnetic parameters is explained in terms of intermolecular hydrogen bonding to the halogen. Attention is focused on nitrogen-halogen a* radicals in Chapter Four, where they are shown to be radiolytically formed in ammonium halides, mono, di and trialkylammonium iodides and monoalkylammonium bromides. Alkylamanium chloride radicals could not be identified. Chapter Five primarily explores the effect of the halide counter ion on the solid-state radiolysis of some tetraalkylammonium, trialkylsulphonium and trialkylsulphoxonium cations. During the course of the investigation, sulphur-halogen a* radicals are identified in the trialkylsulphonium salts after annealing. The last chapter investigates the factors which determine the type of species formed following electron capture by carbon halogen bonds. Both adducts and a* radicals are characterised and with particular reference to the specific example of iodoacetamide, consideration is given to the factors influencing their stability.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.235163  DOI: Not available
Keywords: Radiation induced defects
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