Photoionisation of the tropyl radical

We present a study on the photoionisation of the cycloheptatrienyl (tropyl) radical, C7H7, using tunable vacuum ultraviolet synchrotron radiation. Tropyl is generated by flash pyrolysis from bitropyl. Ions and electrons are detected in coincidence, permitting us to record mass-selected photoelectron spectra. The threshold photoelectron spectrum of tropyl, corresponding to the X + 1A1’ ← X 2E2” transition, reveals an ionisation energy of 6.23 ± 0.02 eV, in good agreement with Rydberg extrapolations, but slightly lower than the value derived from earlier photoelectron spectra. Several vibrations can be resolved and are reassigned to the C–C stretch mode ν16 + and to a combination of ν16 + with the ring breathing mode ν2 +. Above 10.55 eV dissociative photoionisation of tropyl is observed, leading to the formation of C5H5 + and C2H2.

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Progress in Fixed-Photon-Energy Time-Efficient Double Imaging Photoelectron/Photoion Coincidence Measurements in Quantitative Flame Analysis

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2016-0760 ◽

2016 ◽

Vol 230 (8) ◽

Cited By ~ 11

Author(s):

Daniel Felsmann ◽

Arnas Lucassen ◽

Julia Krüger ◽

Christian Hemken ◽

Luc-Sy Tran ◽

...

Keyword(s):

Mass Spectrometry ◽

Synchrotron Radiation ◽

Photon Energy ◽

Molecular Beam ◽

Vacuum Ultraviolet ◽

Photoelectron Spectra ◽

Combustion Analysis ◽

Molecular Beam Mass Spectrometry ◽

Vuv Photoionization ◽

Coincidence Measurements

AbstractPhotoelectron photoion coincidence (PEPICO) spectroscopy as an attractive new technique for combustion analysis was used in a fixed-photon-energy configuration to provide quantitative species profiles in laminar premixed flames. While such measurements are conventionally performed with molecular-beam mass spectrometry (MBMS) using electron ionization (EI) or vacuum ultraviolet (VUV) photoionization (PI) with synchrotron radiation, these techniques have some limitations. The possibility to record photoelectron spectra (PES) simultaneously with photoionization data, providing fingerprint information for reliable species identification, presents a significant advantage of PEPICO spectroscopy especially in complex reactive mixtures. The multiplex approach presented here, enhanced by the imaging capabilities of the electron and ion detection in the so-called double-imaging PEPICO scheme (i

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PHOTOIONIZATION THRESHOLD STRUCTURE OF FULLERENES: VIBRATIONAL EXCITATION

Surface Review and Letters ◽

10.1142/s0218625x96001406 ◽

1996 ◽

Vol 03 (01) ◽

pp. 781-784 ◽

Cited By ~ 1

Author(s):

H. STEGER ◽

J. de VRIES ◽

A. HIELSCHER ◽

W. KAMKE ◽

I.V. HERTEL

Keyword(s):

Vibrational Excitation ◽

Threshold Region ◽

Vibrational Modes ◽

Breathing Mode ◽

Stretch Mode ◽

Good Agreement

The threshold region of the photoionization spectra of fullerenes shows distinct changes of slope which are typical for the opening of additional channels due to vibrational excitation. Typically, after evaporation from a hot oven, C 60 is excited in all its vibrational modes. Through coupling with the ionization transition only the two highly symmetric modes (breathing mode and tangential stretch mode) can be excited or de-excited. An analysis of the C 60 data reveals very good agreement of the observed structure with the expected energetic positions of various combinations of excitation and de-excitation of these two modes.

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Variable-energy photoelectron spectroscopy of CpM(CO)3 (M = Mn, Re) and CpFe(CO)2I

Canadian Journal of Chemistry ◽

10.1139/v96-252 ◽

1996 ◽

Vol 74 (11) ◽

pp. 2240-2249 ◽

Cited By ~ 3

Author(s):

Yong-Feng Hu ◽

G. Michael Bancroft ◽

Kim H. Tan ◽

John S. Tse ◽

Dong-Sheng Yang

Keyword(s):

Synchrotron Radiation ◽

Transition Metal Complexes ◽

Photoelectron Spectroscopy ◽

General Trend ◽

Resonance Effect ◽

Photoelectron Spectra ◽

Ligand Field ◽

Band Spectra ◽

Variable Energy ◽

Good Agreement

Photoelectron spectra of the valence, inner-valence, and core levels of CpM(CO)3 (M = Mn, Re) and CpFe(CO)2I were obtained using He I radiation and synchrotron radiation between 21 eV and 150 eV photon energies. The high-resolution Mn 3p, Fe 3p, and I 4d core level spectra are reported. Broadening of the I 4d spectrum is due to vibrational and ligand field splittings. Observation of the 3p spectra is critical to fully interpreting the np → nd resonance effect in the valence band spectra. This resonance effect is very useful for assigning the metal d orbital bands in the valence spectra. A Xα-SW calculation of CpMn(CO)3 was used to confirm the assignment of the valence and inner-valence orbitals. The experimental and theoretical branching ratios are in good agreement. The general trend of the metal d orbital ionization potentials for CpML3 (M = transition metal) complexes is also discussed. Key words: photoelectron, synchrotron radiation, CpMn(CO)3, CpRe(CO)3, CpFe(CO)2I, np → nd resonance, Xα-SW calculation.

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Oscillator Strength Measurements in the Vacuum-Ultraviolet by the Emission Method

International Astronomical Union Colloquium ◽

10.1017/s0252921100108073 ◽

1988 ◽

Vol 102 ◽

pp. 353-356

Author(s):

C. Goldbach ◽

G. Nollez

Keyword(s):

Oscillator Strength ◽

Vacuum Ultraviolet ◽

Oscillator Strengths ◽

Emission Method ◽

Absolute Scale ◽

Good Agreement

AbstractThe principles and the realization of an experiment devoted to oscillator strength measurements in the vacuum-ultraviolet by the emission method are briefly presented. The results obtained for the strong multiplets of neutral nitrogen and carbon in the 1200-2000 Å range yield an absolute scale of oscillator strengths in good agreement with the most recent calculations.

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VACUUM ULTRAVIOLET AND SOFT X-RAY BROADBAND MONOCHROMATOR FOR A SYNCHROTRON RADIATION METROLOGICAL STATION

Автометрия ◽

10.15372/aut20190201 ◽

2019 ◽

Keyword(s):

Synchrotron Radiation ◽

Vacuum Ultraviolet ◽

X Ray

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Kinetics of 1- and 2-methylallyl + O2 reaction, investigated by photoionisation using synchrotron radiation

Physical Chemistry Chemical Physics ◽

10.1039/d0cp05441k ◽

2021 ◽

Author(s):

Domenik Schleier ◽

Engelbert Reusch ◽

Marius Gerlach ◽

Tobias Preitschopf ◽

Deb Pratim Mukhopadhyay ◽

...

Keyword(s):

Synchrotron Radiation ◽

Reaction Kinetics ◽

Molecular Oxygen ◽

Light Source ◽

Storage Ring ◽

Vacuum Ultraviolet ◽

Flow Tube ◽

Tube Reactor ◽

Swiss Light Source ◽

Kinetics Of

The reaction kinetics of the isomers of the methylallyl radical with molecular oxygen has been studied in a flow tube reactor at the vacuum ultraviolet (VUV) beamline of the Swiss Light Source storage ring.

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