{"id":{"repo_id":"freiburg-diss","oai_identifier":"oai:freidok.uni-freiburg.de:557"},"canonical_url":"https://search.dev.ndltd.org/etd/freiburg-diss/oai:freidok.uni-freiburg.de:557","repository":{"repo_id":"freiburg-diss","name":"University of Freiburg","base_url":"https://freidok.uni-freiburg.de/oai/oai2.php"},"display":{"title":"Exotic Species of Hydrogen","abstract":"This thesis deals with experimental and theoretical investigations of the triatomic molecule H3 and the negative ion of Hydrogen H-. These 'exotic' systems of Hydrogen are known to have a rather instable character due to their strong internal coupling and correlation phenomena. Their astrophysical significance and their role as exemplary cases in fundamental research justify the great interest that is devoted to them in many scientific disciplines. In Part I, a full account of the structure and dynamics of the simplest, polyatomic molecule H3 is given. While for close-coupled states the electronic motion follows the vibrational and rotational nuclear motion adiabatically implying the validity of the Born-Oppenheimer approach, this principle is strictly violated for higher electronically excited states. This latter energy domain might be interpreted by a collision-like picture between the tumbling and vibrating parent ion and the incoming Rydberg electron, enabling exchange of energy and angular momentum during their short-range interaction. We apply the most advanced approach known today for such processes to predict spectra on an ab initio basis and for a comparison with our experimental data. In Part II of this thesis, we investigate photodetachment processes of the negative Hydrogen ion in strong laser-field regimes. A Keldysh-Faisal-Reiss theory allows semiclassical interpretations of complex ionization mechanisms in strong laser-fields due to its conformity with the Feynman path integral formalism. We employ a new kind of photoelectron imaging that maps continuous wavefunctions generated from a fast atomic beam in the focal area of an intense laser onto a 2D detector. The method permits a full reconstruction of the wavefunction by means of numerical inversion of the projected distributions. A series of excess photon detachment channels by non-linear laser-matter interactions and a quantum path interference effect in H- is observed for the first time.","abstract_html":"This thesis deals with experimental and theoretical investigations of the triatomic molecule H3 and the negative ion of Hydrogen H-. These 'exotic' systems of Hydrogen are known to have a rather instable character due to their strong internal coupling and correlation phenomena. Their astrophysical significance and their role as exemplary cases in fundamental research justify the great interest that is devoted to them in many scientific disciplines. In Part I, a full account of the structure and dynamics of the simplest, polyatomic molecule H3 is given. While for close-coupled states the electronic motion follows the vibrational and rotational nuclear motion adiabatically implying the validity of the Born-Oppenheimer approach, this principle is strictly violated for higher electronically excited states. This latter energy domain might be interpreted by a collision-like picture between the tumbling and vibrating parent ion and the incoming Rydberg electron, enabling exchange of energy and angular momentum during their short-range interaction. We apply the most advanced approach known today for such processes to predict spectra on an ab initio basis and for a comparison with our experimental data. In Part II of this thesis, we investigate photodetachment processes of the negative Hydrogen ion in strong laser-field regimes. A Keldysh-Faisal-Reiss theory allows semiclassical interpretations of complex ionization mechanisms in strong laser-fields due to its conformity with the Feynman path integral formalism. We employ a new kind of photoelectron imaging that maps continuous wavefunctions generated from a fast atomic beam in the focal area of an intense laser onto a 2D detector. The method permits a full reconstruction of the wavefunction by means of numerical inversion of the projected distributions. A series of excess photon detachment channels by non-linear laser-matter interactions and a quantum path interference effect in H- is observed for the first time.","abstract_has_math":false,"creators":["Reichle, Rainer"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Helm, Hanspeter"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":null,"date_issued":"","date_published":null,"updated_at":"2026-07-24T02:21:46Z","subjects":["Intramolekulare Elektron-Ion Stösse","Vielkanalwechselwirkung","NichtlineareAtom-Laser Ww","Quantenpfadinterferenzen","Abbildungsverfahren","Intramolecular electron-ion collisions","Multichannel Interactions","Nonlinear Atom-Laser Interactions","Quantum Path Interferences"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://freidok.uni-freiburg.de/data/557","outbound_label":"Repository record","outbound_source":"source_url"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Helm, Hanspeter"]},{"key":"dc:creator","label":"Author","values":["Reichle, Rainer"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:type","label":"Dc Type","values":["DoctoralThesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Intramolekulare Elektron-Ion Stösse","Vielkanalwechselwirkung","NichtlineareAtom-Laser Ww","Quantenpfadinterferenzen","Abbildungsverfahren","Intramolecular electron-ion collisions","Multichannel Interactions","Nonlinear Atom-Laser Interactions","Quantum Path Interferences"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["This thesis deals with experimental and theoretical investigations of the triatomic molecule H3 and the negative ion of Hydrogen H-. These 'exotic' systems of Hydrogen are known to have a rather instable character due to their strong internal coupling and correlation phenomena. Their astrophysical significance and their role as exemplary cases in fundamental research justify the great interest that is devoted to them in many scientific disciplines. In Part I, a full account of the structure and dynamics of the simplest, polyatomic molecule H3 is given. While for close-coupled states the electronic motion follows the vibrational and rotational nuclear motion adiabatically implying the validity of the Born-Oppenheimer approach, this principle is strictly violated for higher electronically excited states. This latter energy domain might be interpreted by a collision-like picture between the tumbling and vibrating parent ion and the incoming Rydberg electron, enabling exchange of energy and angular momentum during their short-range interaction. We apply the most advanced approach known today for such processes to predict spectra on an ab initio basis and for a comparison with our experimental data. In Part II of this thesis, we investigate photodetachment processes of the negative Hydrogen ion in strong laser-field regimes. A Keldysh-Faisal-Reiss theory allows semiclassical interpretations of complex ionization mechanisms in strong laser-fields due to its conformity with the Feynman path integral formalism. We employ a new kind of photoelectron imaging that maps continuous wavefunctions generated from a fast atomic beam in the focal area of an intense laser onto a 2D detector. The method permits a full reconstruction of the wavefunction by means of numerical inversion of the projected distributions. A series of excess photon detachment channels by non-linear laser-matter interactions and a quantum path interference effect in H- is observed for the first time."]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Exotic Species of Hydrogen","Exotische Arten von Wasserstoff"]}]}],"canonical_facts":{"dc:contributor":["Helm, Hanspeter"],"dc:creator":["Reichle, Rainer"],"dc:description.abstract":["This thesis deals with experimental and theoretical investigations of the triatomic molecule H3 and the negative ion of Hydrogen H-. These 'exotic' systems of Hydrogen are known to have a rather instable character due to their strong internal coupling and correlation phenomena. Their astrophysical significance and their role as exemplary cases in fundamental research justify the great interest that is devoted to them in many scientific disciplines. In Part I, a full account of the structure and dynamics of the simplest, polyatomic molecule H3 is given. While for close-coupled states the electronic motion follows the vibrational and rotational nuclear motion adiabatically implying the validity of the Born-Oppenheimer approach, this principle is strictly violated for higher electronically excited states. This latter energy domain might be interpreted by a collision-like picture between the tumbling and vibrating parent ion and the incoming Rydberg electron, enabling exchange of energy and angular momentum during their short-range interaction. We apply the most advanced approach known today for such processes to predict spectra on an ab initio basis and for a comparison with our experimental data. In Part II of this thesis, we investigate photodetachment processes of the negative Hydrogen ion in strong laser-field regimes. A Keldysh-Faisal-Reiss theory allows semiclassical interpretations of complex ionization mechanisms in strong laser-fields due to its conformity with the Feynman path integral formalism. We employ a new kind of photoelectron imaging that maps continuous wavefunctions generated from a fast atomic beam in the focal area of an intense laser onto a 2D detector. The method permits a full reconstruction of the wavefunction by means of numerical inversion of the projected distributions. A series of excess photon detachment channels by non-linear laser-matter interactions and a quantum path interference effect in H- is observed for the first time."],"dc:format.medium":["application/pdf"],"dc:subject":["Intramolekulare Elektron-Ion Stösse","Vielkanalwechselwirkung","NichtlineareAtom-Laser Ww","Quantenpfadinterferenzen","Abbildungsverfahren","Intramolecular electron-ion collisions","Multichannel Interactions","Nonlinear Atom-Laser Interactions","Quantum Path Interferences"],"dc:title":["Exotic Species of Hydrogen","Exotische Arten von Wasserstoff"],"dc:type":["DoctoralThesis"]},"updated_at":"2026-07-24T02:21:46Z"}