Two Studies in Gas-Phase Ion Spectroscopy

This report covers two investigations into gas-phase ion spectroscopy; the first using tunable vacuum-ultraviolet radiation to identify negative ions from photoexcited polyatomic molecules, and the second studying ion flow tube mass spectrometry.

In this thesis Matthew Simpson reportstwo areas of work in gas ion spectroscopy, each investigation in itself worthy of a PhD. The first study uses tunable vacuum-ultraviolet radiation from a synchrotron to identify negative ions from twenty four photoexcited polyatomic molecules in the gas phase. From these experiments, Matthew collects a vast amount of data and summarises and reviews ion-pair formation from polyatomic molecules. The second study is on selected ion flow tube mass spectrometry. Matthew investigates the reactions of cations and anions with ethene, monofluoroethene, 1,1-difluoroethene and tetrafluoroethene. In this study Matthew tries to explain why certain products are formed preferentially over other products at a microscopic level of understanding. The data recorded in this thesis form the most comprehensive collection of information about anion formation and are the basis of a review and numerous articles in specialist journals.

Nominated by the University of Birmingham for a Springer Theses Prize. From a huge quantity of data the author attempts to rationalise the circumstances needed for favourable formation of anions The most comprehensive collection of information on this type of ion formation Includes supplementary material: sn.pub/extras

Texte du rabat
In this thesis Matthew Simpson reports two areas of work in gas ion spectroscopy, each investigation in itself worthy of a PhD. The first study uses tunable vacuum-ultraviolet radiation from a synchrotron to identify negative ions from twenty four photoexcited polyatomic molecules in the gas phase. From these experiments, Matthew collects a vast amount of data and summarises and reviews ion-pair formation from polyatomic molecules. The second study is on selected ion flow tube mass spectrometry. Matthew investigates the reactions of cations and anions with ethene, monofluoroethene, 1,1-difluoroethene and tetrafluoroethene. In this study Matthew tries to explain why certain products are formed preferentially over other products at a microscopic level of understanding. The data recorded in this thesis form the most comprehensive collection of information about anion formation and are the basis of a review and numerous articles in specialist journals.

Contenu
Introduction and background information.- The experiments.- Vacuum-ultraviolet negative photoion spectroscopy of SF 6 , CF 4 and SF 5 CF 3 .- Vacuum-ultraviolet negative photoion spectroscopy of CF 3 Cl, CF 3 Br and CF 3 I.- Vacuum-ultraviolet negative photoion spectroscopy of SF 5 Cl.- Vacuum-ultraviolet negative photoion spectroscopy of small polyatomic molecules.- The reactions of CF n + (n = 1-3) with C 2 H 4 , C 2 H 3 F, CH 2 CF 2 and C 2 HF 3 .- The reactions of C 2 F 4 + with C 2 H 4 , C 2 H 3 F, CH 2 CF 2 and C 2 HF 3 .- Reactions of OH - , O - , CF 3 - , F - and O 2 - with C 2 H 4 , C 2 H 3 F, CH 2 CF 2 , C 2 HF 3 and C 2 F 4 .