References of "Locht, Robert"
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See detailA Mass Spectrometric Photoionization Study of CH3F. The CH2+, CH3+ and CH2F+ Ion Formation.
Locht, Robert ULg; Momigny, J.; Rühl, E. et al

in Chemical Physics (1987), 117

The decay of CH3F+ in the CH2+, CH3+ and CH2F+ dissociation channels has been investigated by photoionization mass spectrometry using synchrotron radiation in the energy range 10-25 eV. The ... [more ▼]

The decay of CH3F+ in the CH2+, CH3+ and CH2F+ dissociation channels has been investigated by photoionization mass spectrometry using synchrotron radiation in the energy range 10-25 eV. The photoabsorption curve of CH3F and the ionization efficiency curves of CH2+, CH3+ and CH2F+ as well as the kinetic energy-versus-appearance energy diagram for CH3+ were recorded. For the three fragment ions dissociative autoionization is a prominent formation process. Direct dissociative ionization is observed for the same ions through the decomposition of the CH3F+(A2A1+B2E) states at 16.1 eV as well as presumably of the C2A1 state at about 22.5 eV. [less ▲]

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See detailThe Dissociative Photoionization of O2 and N2O.
Locht, Robert ULg; Hagenow, G.; Rühl, E. et al

Book published by Berliner Elektronen Speicherring für Synchrotron Strahlung m.b.H. (BESSY) - Jahresbericht/Annual Report (1987)

The dissociative photoionization of O2 and N2O is investigated using synchrotron radiation. The results on the O+ and NO+ dissociation channels are reported.

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See detailThe Dissociative Ionization of CH3F. A Mass Spectrometric Photoionization study using Synchrotron Radiation.
Locht, Robert ULg; Rühl, E.; Momigny, J. et al

in Gilbody, H. B.; Newell, W. R.; Read, F. H. (Eds.) et al Electronic and Atomic Collisions: Abstracts of Contributed Papers. (1987)

The dissociation channel of CH3F+hnu->CH3++F has been investigated by photoionization using synchrotron radiation. The kinetic energy-versus-appearance energy diagram of CH3+ has been reported and ... [more ▼]

The dissociation channel of CH3F+hnu->CH3++F has been investigated by photoionization using synchrotron radiation. The kinetic energy-versus-appearance energy diagram of CH3+ has been reported and analyzed. [less ▲]

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See detailThe Dissociative Photoionization of CH3F.
Locht, Robert ULg; Rühl, E.; Momigny, J. et al

Book published by Berliner Elektronen Speicherring für Synchrotron Strahlung m.b.H. (BESSY) (1987)

The kinetic energy distributions of CH3+/CH3F are measured at different wavelengths using monochromatized synchrotron radiation. The ionization efficiency curves of CH3+ are measured for different kinetic ... [more ▼]

The kinetic energy distributions of CH3+/CH3F are measured at different wavelengths using monochromatized synchrotron radiation. The ionization efficiency curves of CH3+ are measured for different kinetic energies. The resulting kinetic energy-versus-appearance energy is reported. [less ▲]

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See detailThe Dissociative Electroionization of NH3. The NH+ Dissociation Channel.
Locht, Robert ULg; Servais, Christian ULg; Ligot, M. et al

in Gilbody, H. B.; Newell, W. R.; Read, F. H. (Eds.) et al Electronic and Atomic Collisions: Abstracts of Contributed Papers. 15th International Conference on the Physics of Electronic and Atomic Collisions. Brighton, United Kingdom, 1987. (1987)

The dissociative electoionization efficiency of Nh3 in the NH+ channel is reported. The kinetic energy of this fragment ion is measured as a function of the impinging electron energy. Several dissociation ... [more ▼]

The dissociative electoionization efficiency of Nh3 in the NH+ channel is reported. The kinetic energy of this fragment ion is measured as a function of the impinging electron energy. Several dissociation limits are detected. [less ▲]

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See detailA versatile low-cost Automation System for an Electroionization Experiment.
Servais, Christian ULg; Locht, Robert ULg; Momigny, J.

in International Journal of Mass Spectrometry and Ion Processes (1986), 74

A cheap complete automation system designed for an electoionization experiment is described. This system is based on a Sinclair ZX Spectrum computer and a modular architecture. The control program and ... [more ▼]

A cheap complete automation system designed for an electoionization experiment is described. This system is based on a Sinclair ZX Spectrum computer and a modular architecture. The control program and general building blocks diagrams are discussed and give a general idea of how to build modules or procedures adapted to different applications. [less ▲]

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See detailTranslational Energy Disposal and Mechanisms of Unimolecular Dissociative Photoionization with He(I) and Ne(I) Resonance Lines. A Surprisal Ananlysis of the CH3F->CH3++F Process.
Momigny, J.; Locht, Robert ULg; Caprace, G.

in International Journal of Mass Spectrometry and Ion Processes (1986), 71

The He(I) and Ne(I) photoions translational energy spectra of CH3+ from CH3F were measured. At both wavelengths, the translational energy spectrum is made of two components. Their surpisal analysis shows ... [more ▼]

The He(I) and Ne(I) photoions translational energy spectra of CH3+ from CH3F were measured. At both wavelengths, the translational energy spectrum is made of two components. Their surpisal analysis shows two distinct behaviours: (i) the low energetic and narrow component exhibits a positive slope, whereas (ii) the high energetic and widely spread component is characterized by a negative slope. Furthermore, when He(I) is used, the high translational energy distribution shows a multimodal surprisal. These observations as well as the origin of both distributions are discussed. [less ▲]

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See detailThe Dissociative Ionization of Methyl Fluoride. The formation of CH2+ and CH3+.
Locht, Robert ULg; Momigny, J.

in International Journal of Mass Spectrometry and Ion Physics (1986), 71

The decay of ionized CH3F was investigated in the CH2+ and CH3+ dissiciation channels by electronionization and fixed wavelength photoionization using HeI and NeI resonance lines. The translational energy ... [more ▼]

The decay of ionized CH3F was investigated in the CH2+ and CH3+ dissiciation channels by electronionization and fixed wavelength photoionization using HeI and NeI resonance lines. The translational energy spectra, ionization efficiency curves and kinetic energy-versus-appearance enegy diagrams of both ions were measured. Although dissociative autoionization is the prominent dissociation mechanism for the appearance of CH2+ and CH3+, direct dissociative ionization is observed for CH2+ at 23.4 eV and for CH3+ at 16.5 eV. [less ▲]

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See detailMechanism for the Appearance of H+ by Electroionization of CH4. A Surprisal Analysis.
Momigny, J.; Locht, Robert ULg; Caprace, G.

in Chemical Physics (1986), 102

Previous experimental results on the threshold energy and on the energy range of the first wide translational energy distribution of H+, resulting from the electron impact on CH4, are interpreted. The ... [more ▼]

Previous experimental results on the threshold energy and on the energy range of the first wide translational energy distribution of H+, resulting from the electron impact on CH4, are interpreted. The translational energy surprisal of this distribution has been evaluated with respect to a statistically calculated one. The surprisal plot shows a fourth power dependence on fT with a negative slope associated with a large DeltaS/exc value of about 4 eu. An "a priori" calculated P(ET/E) distribution, including four constraints, fits fairly well the observed translational energy distribution. [less ▲]

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See detailAbout the Kinetic Energy Spectra of Fragment Ions. A comparison between Electroionization and fixed-wavelength Photoionization.
Locht, Robert ULg; Momigny, J.

in Lahmani, Françoise; Castex, M. C.; Collin, Jacques (Eds.) et al Photophysics and Photochemistry above 6 eV. (1985)

The HeI and NeI translational energy spectra have been recorded for NO+/N2O and CH3+/CH3F. The marked difference between the two spectra for NO+ is related to the NeI-A2Sigma+ photoelectron spectrum. Both ... [more ▼]

The HeI and NeI translational energy spectra have been recorded for NO+/N2O and CH3+/CH3F. The marked difference between the two spectra for NO+ is related to the NeI-A2Sigma+ photoelectron spectrum. Both spectra of CH3+ show two components, i.e. a thermal peak and a high energy distribution. As the energetic ions are ascribed to the decomposition of the CH3F+(2E+2A1) states the thermal ions could be interpreted by the dissociation of the CH3F+(X2E) state. [less ▲]

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See detailA Dissociative Electroionization Study of Nitrous Oxide. The O+ and N+ Dissociation channels.
Olivier, J. L.; Locht, Robert ULg; Momigny, J.

in Chemical Physics (1984), 84

After the investigation of the decay of N2O into NO+ and N2+ the dissociation channels leading to O+ and N+ are examined by electroionization using ion kinetic energy and mass analysis. Appearance ... [more ▼]

After the investigation of the decay of N2O into NO+ and N2+ the dissociation channels leading to O+ and N+ are examined by electroionization using ion kinetic energy and mass analysis. Appearance energies of O+ and N+ are measured as a function of the kinetic energy of the fragment ions. Predissociation is the main mechanism for ion production in both channels. In the O+ decay channel the 4Sigma- state is an important intermediate. The neutral N2(X1Sigma+/g) mainly appears vibrationally excited. In the N+ dissociation channel, 2Pi states have to play an important role by predissociating the N2O(C2Sigma+) state and the higher-lying doubly excited states of N2O+. [less ▲]

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See detailThe Dissociative Ionization of Nitrous Oxide. A comparison between Electroionization and HeI and NeI Photoionization.
Locht, Robert ULg; Caprace, G.; Momigny, J.

in Chemical Physics Letters (1984), 111

The photoelectron spectrum of N2O and the kinetic energy distributions of NO+, N2+, O+ and N+ have been recorded with HeI and NeI resonance lines. At 21.22 eV the distributions are similar to those ... [more ▼]

The photoelectron spectrum of N2O and the kinetic energy distributions of NO+, N2+, O+ and N+ have been recorded with HeI and NeI resonance lines. At 21.22 eV the distributions are similar to those observed by electroionization at comparable energy. The NeI resonance line produces O+ and NO+ ions. Their respective kinetic energy distributions are related to the change induced in the N2O+(A2Sigma+) photoelectron band excited by the NeI resonance line. [less ▲]

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See detailThe Dissociative ionization of Nitrous Oxide. An Electroionization Study.
Olivier, J. L.; Locht, Robert ULg; Momigny, J.

in International Journal of Mass Spectrometry and Ion Physics (1984), 58

The dissociative electroionization of nitrous oxide into its four dissociation channels has been studied by a method using the kinetic energy and mass analysis. The formation of N2+, NO+, O+ and N+ are ... [more ▼]

The dissociative electroionization of nitrous oxide into its four dissociation channels has been studied by a method using the kinetic energy and mass analysis. The formation of N2+, NO+, O+ and N+ are discussed essentially in terms of predissociation of the ground and excited N2O+ states between 15 and 40 eV. In most cases the predissociating states are also identified. The present results are compared with those in the literature. [less ▲]

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See detailThe O+ and N+ Formation by low-energy Electron Impact on Nitrous Oxide.
Olivier, J. L.; Locht, Robert ULg; Momigny, J.

in Eichler, J.; Fritsch, W.; Hertel, I. V. (Eds.) et al Electronic and Atomic Collisions: abstracts of contributed papers. (1983)

The O+ and N+ dissociation channels in N2O have been investigated by electroionization using ion kinetic energy and mass analysis. Appearance enegies are measured as a function of the translational energy ... [more ▼]

The O+ and N+ dissociation channels in N2O have been investigated by electroionization using ion kinetic energy and mass analysis. Appearance enegies are measured as a function of the translational energy of the fragment ions. The different dissociation mechanisms are discussed. [less ▲]

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See detailThe Dissociative Electroionization of Nitrous Oxide. The O+ Dissociation Channel.
Olivier, J. L.; Locht, Robert ULg; Momigny, J.

in International Journal of Mass Spectrometry and Ion Physics (1983), 46

By electroionization mass spectrometry and ion kinetic energy analysis, the O+ fragment ion formation from N2O has been analyzed. Different appearance energies are measured and interpreted. Between the ... [more ▼]

By electroionization mass spectrometry and ion kinetic energy analysis, the O+ fragment ion formation from N2O has been analyzed. Different appearance energies are measured and interpreted. Between the onset at 15.27 eV and 22 eV only two dissociation limits are involved, i.e. O+(4S)+N2(X1Sigma+/g) at 15.29 eV and O+(2D)+N(X1Sigma+/g) at 18.61 eV. In both cases N2(X1Sigma+/g) is produced in its v=0 up to v=8 vibrational levels. Predissociation of ionic and Rydberg states of N2O are the dominant processes. [less ▲]

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See detailA Dissociative Electroionization Study of Nitrous Oxide. The NO+ and N2+ Dissociation Channels.
Olivier, J. L.; Locht, Robert ULg; Momigny, J.

in Chemical Physics (1982), 68

The decay of N2O into NO+ and N2+ dissociation channels has been investigated by electron impact using ions kinetic energy and mass analysis. The appearance energies of NO+ and N2+ are measured as a ... [more ▼]

The decay of N2O into NO+ and N2+ dissociation channels has been investigated by electron impact using ions kinetic energy and mass analysis. The appearance energies of NO+ and N2+ are measured as a function of the released translational energy. Both decay channels are mainly reached through predissociation of the N2O+ ionic states. In the NO+ decay channel, only one dissociation limit is involved, i.e. NO+(X1Sigma+,v)+N(4S) and hence the repulsive 4Sigma- state is responsible for all the observed phenomena. In the N2+ decay channel, several dissociation limits are involved. Dissociative ionization involving doubly excited states of N2O+ in both dissociation channels are briefly discussed. [less ▲]

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See detailThe Dissociative Electroionization of Nitrous Oxide. The N+ and O+ Dissociation Channels.
Locht, Robert ULg; Olivier, J. L.; Momigny, J.

in Schmid, E. R. (Ed.) Book of Abstracts of the 9th International Mass Spectrometry Conference (1982)

The first results on the dissociative elctroionization of nitrous oxide in the N+ and O+ dissociation channels are reported in the 15-32 eV electron energy range. Dissociation mechanisms at several ... [more ▼]

The first results on the dissociative elctroionization of nitrous oxide in the N+ and O+ dissociation channels are reported in the 15-32 eV electron energy range. Dissociation mechanisms at several critical energies are presented. [less ▲]

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See detailThe Dissociative Ionization of N2O by low energy Electron Impact: the N+ and N2+ Dissociation Channels.
Locht, Robert ULg; Olivier, J. L.; Beeckman, W. et al

in XII International Conference on the Physics of Electronic and Atomic Collisions: Abstracts of Contributed Papers. (1981)

The kinetic energy-versus-appearance energy diagram obtained for N+ and N2+ from N2O by electron impact is discussed.

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See detailThe rotational Predissociation of the CH4+ ion.
Flamme, J.P.; Wankenne, H.; Locht, Robert ULg et al

in "Les Spectres des Molecules simples au Laboratoire et en Astrophysique" (1980)

The kinetic energy release distribution of the metastable transition corresponding to CH(D)4+->CH(D)3+ + H(D) dissociation has been measured using a duoplasmatron coupled with a tandem mass spectrometer ... [more ▼]

The kinetic energy release distribution of the metastable transition corresponding to CH(D)4+->CH(D)3+ + H(D) dissociation has been measured using a duoplasmatron coupled with a tandem mass spectrometer. The metastable peak is modulated by discrete energy states assigned to vibro-rotational levels of CH(D)4+. [less ▲]

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See detailThe Proton Formation from Methane by Dissociative Ionization in the Electron Energy range of 25-40 eV.
Locht, Robert ULg; Momigny, J.

in Chemical Physics (1980), 49

The proton formation by dissociative electroionization of methane has been investigated in the energy range of 25-40 eV. The kinetic energy-versus-appearance energy shows five different H+ producing ... [more ▼]

The proton formation by dissociative electroionization of methane has been investigated in the energy range of 25-40 eV. The kinetic energy-versus-appearance energy shows five different H+ producing processes respectively at (26.3+/0.2) eV, (26.9+/-0.2) eV, (29.4+/-0.3) eV, (32.7+/-0.2) eV and (35.7+/-0.5) eV. These critical energies are discussed in terms of different dissociation channels opened through predissociation of doubly excited states of CH4+. On the high energy side of the electron energy range in the present work, the proton would appear through the dissociation of the CH+ ion as an intermediate. [less ▲]

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