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dc.contributor.advisorLohmann, Birgit
dc.contributor.authorAtkins, Danielle S
dc.date.accessioned2018-01-23T02:56:04Z
dc.date.available2018-01-23T02:56:04Z
dc.date.issued2007
dc.identifier.doi10.25904/1912/2380
dc.identifier.urihttp://hdl.handle.net/10072/367729
dc.description.abstractThe electron-electron coincidence (e,2e) technique yields complete kinematical information about the electron impact ionization process. The (e,2e) technique has been widely used to study dynamical effects in ionizing collisions with atomic targets, however studies of molecular ionization using this technique have been very limited. Recently further experimental studies of small molecules have been proposed, as the cross sections of small molecules are now computable using sophisticated theoretical approaches [77, 24]. This thesis presents dynamical investigations for the electron impact ionization of the molecular targets H2O and H2, employing the (e,2e) technique to experimentally measure the triple differential cross section (TDCS). The TDCS is defined as the probability that a bound electron will be ejected from the target atom or molecule (into a particular direction with a defined energy) and the initial electron will be scattered into a particular direction with a particular energy. All TDCSs presented within this thesis were performed using an electron coincidence spectrometer in the coplanar asymmetric geometry at intermediate incident electron energies. This thesis presents the electron impact ionization TDCSs of H2O. A series of measurements were performed using H2O in the vapour form. Measurements of the TDCS are presented for the 2a1 atomic-like orbital and the 1b2, 3a1 and 1b1 molecular orbitals at a common incident electron energy of 250eV, ejected electron energy of 10eV and scattering angle of -15o. The experimental TDCSs are compared with theoretical cross sections that were calculated by Champion et al [25, 26] using a distorted wave Born approach (DWBA). TDCS measurements for the single ionization of the hydrogen molecule, H2 were performed as in recent years there has been evidence that indicates the ejected electron angular distribution is perturbed due to Young-type interference effects. The oscillatory structure which is predicted in the cross section is due to the two-centred nature of the molecule [27, 29]. This thesis presents experimental TDCSs for the ionization of H2 which are compared to TDCSs of helium. A series of measurements for the TDCSs of H2 and He are presented at a common incident electron energy of 250eV and scattering angle of -15o, for a range of ejected electron energies between 10eV and 100eV. The experimental TDCSs are compared with two types of theoretical calculations.
dc.languageEnglish
dc.publisherGriffith University
dc.publisher.placeBrisbane
dc.rights.copyrightThe author owns the copyright in this thesis, unless stated otherwise.
dc.subject.keywordsmolecular ionization
dc.subject.keywordsmolecules
dc.subject.keywordstriple differential cross section (TDCS)
dc.subject.keywordselectron coincidence spectrometer
dc.titleElectron Coincidence Studies of Molecules
dc.typeGriffith thesis
gro.facultyFaculty of Science, Environment, Engineering and Technology
gro.rights.copyrightThe author owns the copyright in this thesis, unless stated otherwise.
gro.hasfulltextFull Text
dc.contributor.otheradvisorSang, Robert
dc.rights.accessRightsPublic
gro.identifier.gurtIDgu1315198530956
gro.identifier.ADTnumberadt-QGU20070920.112918
gro.source.ADTshelfnoADT00574
gro.thesis.degreelevelThesis (PhD Doctorate)
gro.thesis.degreeprogramDoctor of Philosophy (PhD)
gro.departmentSchool of Biomolecular and Physical Sciences
gro.griffith.authorAtkins, Danielle S.


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