The Experts below are selected from a list of 282 Experts worldwide ranked by ideXlab platform

Masahiro Kitajima - One of the best experts on this subject based on the ideXlab platform.

Vincent Mckoy - One of the best experts on this subject based on the ideXlab platform.

  • Ion Distributions for Resonance-Enhanced Multiphoton Ionization of ClO
    The Journal of Physical Chemistry, 1995
    Co-Authors: Kwanghsi Wang, Vincent Mckoy
    Abstract:

    Results of theoretical studies of rotationally resolved photoelectron spectra for (2 + 1’) resonance enhanced Multiphoton Ionization (REMPI) of the C ^2Σ^-, D ^2Σ^-, E ^2Σ^-, and F ^2Σ^- Rydberg states of ClO are presented. Cooper minima are predicted to occur in the electronic continua for photoIonization of the D and F states and lead to unusual behavior in the ion rotational distributions. Strong partial wave I mixing is also predicted in the continua for the C and E states due to the nonspherical molecular ion potentials. These Cooper minima and l mixing make the associated photoIonization dynamics quite nonatomiclike.

  • Resonance enhanced Multiphoton Ionization of molecules and molecular fragments
    1994
    Co-Authors: Vincent Mckoy
    Abstract:

    Abstract : We have completed studies of ion rotational distributions produced by resonance enhanced Multiphoton Ionization of excited states of molecules and by single-photon Ionization of ground states of jet-cooled molecules by coherent VUV radiation. The objective of this effort was to provide a robust analysis and prediction of key spectral features of interest in related experimental studies and technological applications of these laser-driven Ionization techniques. Specific achievements include: identification of underlying mechanisms for anomalous behavior of ion rotational distributions in laser Ionization of molecules and molecular fragments, development of schemes for exploiting such anomalous behavior to achieve state-selective production of ions, and providing needed insight into the underlying dynamics of state-resolved molecular photoIonization.

  • Rotationally resolved photoelectron spectra in resonance enhanced Multiphoton Ionization of SiF
    The Journal of Chemical Physics, 1992
    Co-Authors: Kwanghsi Wang, Vincent Mckoy
    Abstract:

    Results of calculations of rotationally resolved photoelectron spectra for resonance enhanced Multiphoton Ionization (REMPI) of SiF via the B ^2Σ^+ (4sσ), C" ^2Σ^+ (4pσ), and C’ ^2Π (4pπ) Rydberg states are reported. In addition to the expected ΔN=even peaks, unusually strong ΔN=±1 transitions are predicted for photoIonization of the B ^2Σ^+ state. These unusual transitions are due to even angular momentum components of the photoelectron matrix element and arise from the formation of Cooper minima in the Ionization channels and strong l mixing in the electronic continuum induced by the nonspherical molecular ion potential. Unexpected ΔN=0,±2 transitions, due to odd wave contributions to the photoelectron matrix element, are also predicted for photoIonization of the C" ^2Σ^+ state. Asymmetrical ion distributions with respect to ΔN=0 are also predicted for the C’ ^2Π state. Cooper minima are predicted to occur in the l=2 wave of the kπ photoelectron channel for the B state and in the l=4 wave of the kσ and kπ channels for the C‘ state. Photoelectron angular distributions provide further insight into the photoIonization dynamics.

  • Studies of resonance enhanced Multiphoton Ionization of molecules
    AIP Conference Proceedings, 1991
    Co-Authors: Vincent Mckoy
    Abstract:

    A discussion is given to studies of Resonance Enhanced Multiphoton Ionization (REMPI) processes in molecules. (AIP)

  • Rotational branching ratios and photoelectron angular distributions in resonance enhanced Multiphoton Ionization of diatomic molecules
    The Journal of Chemical Physics, 1991
    Co-Authors: Kwanghsi Wang, Vincent Mckoy
    Abstract:

    In this paper we extend a previous formulation of molecular resonance enhanced Multiphoton Ionization (REMPI) photoelectron spectra to explicitly include multiplet‐specific final state wave functions and intermediate coupling schemes. The results of this formulation should be well suited and helpful in quantitative theoretical studies of rotationally resolved REMPI spectra in many diatomic molecules of interest. As an example, we use this formulation to study the rotational branching ratios and photoelectron angular distributions for (3+1) REMPI of NH via the 3 3Π Rydberg resonant state. The predicted anomalous rotational distributions are interpreted as arising from a Cooper minimum in the l=2 component of the kπ photoIonization channel. A number of other results are obtained and discussed.

Katharina Titze - One of the best experts on this subject based on the ideXlab platform.

  • Resonance-Enhanced Multiphoton Ionization with circularly polarized light: chiral carbonyls
    Analytical and Bioanalytical Chemistry, 2013
    Co-Authors: Ulrich Boesl, Alexander Bornschlegl, Christoph Logé, Katharina Titze
    Abstract:

    An introduction to the principle and possibilities of the new method of circular dichroism laser mass spectrometry is given and its state of development is reviewed. This method allows enantiosensitive, mass-selective probing of chiral molecules. It is based on the combination of Resonance-Enhanced Multiphoton Ionization with circularly polarized light and specially modified time-of-flight mass spectrometry. As an example, application to carbonyls is presented. Figure The combination of resonance enhanced Multiphoton Ionization and circular dichroism performed in a time-of-flight mass spectrometer allows mass selective enantio-sensitive spectroscopy with new features for chiral analysis

  • Resonance-Enhanced Multiphoton Ionization with circularly polarized light: chiral carbonyls
    Analytical and bioanalytical chemistry, 2013
    Co-Authors: Ulrich Boesl, Alexander Bornschlegl, Christoph Logé, Katharina Titze
    Abstract:

    An introduction to the principle and possibilities of the new method of circular dichroism laser mass spectrometry is given and its state of development is reviewed. This method allows enantiosensitive, mass-selective probing of chiral molecules. It is based on the combination of Resonance-Enhanced Multiphoton Ionization with circularly polarized light and specially modified time-of-flight mass spectrometry. As an example, application to carbonyls is presented.

Jeffrey W. Hudgens - One of the best experts on this subject based on the ideXlab platform.

  • RESONANCE ENHANCED Multiphoton Ionization SPECTROSCOPY OF THE SNF RADICAL
    The Journal of Chemical Physics, 1996
    Co-Authors: Jonathan Pearson, Jeffrey W. Hudgens, Richard N. Dixon, Russell D. Johnson
    Abstract:

    The resonance enhanced Multiphoton Ionization spectrum of the free radical SnF has been recorded using excitation wavelengths in the range 540 to 360 nm. The previously documented C 2Δ, D, E 2Π, and F 2Σ+ states and two hitherto unidentified excited states, the H and I 2Φ states, were all observed as two‐photon resonances. Band contour simulations yielded spectroscopic constants for the E, F, and I states.

  • Resonance enhanced Multiphoton Ionization spectroscopy of the PF radical
    The Journal of Chemical Physics, 1996
    Co-Authors: Jd Howe, Michael N. R. Ashfold, Colin M. Western, Jeffrey W. Hudgens
    Abstract:

    PF radicals in both their ground (X 3Σ−) and metastable (a 1Δ) electronic states have been produced by the gas phase reaction of F atoms with phosphine in a discharge flow reactor and detected by mass selective resonance enhanced Multiphoton Ionization (REMPI) spectroscopy in the wavelength range 410–225 nm. Analysis of the longer wavelength end of this spectrum (λ≳328 nm) has enabled identification and spectroscopic characterization of five hitherto unknown Rydberg states of this radical. These we label the h 1Σ+ (T0=57 324.9 cm−1), D 3Δ (T0=58 223.0 cm−1), E 3Σ− (T0=58 690 cm−1), i 1Δ (T0=59 881.6 cm−1), and j 1Σ− (T0=61 873.9 cm−1) states, respectively. [Origins, relative to the lowest rovibrational level of the ground (X 3Σ−) state are indicated by the numbers in brackets.] Quantum defect arguments suggest that all five states derive from the electronic configuration [2Π]4pπ1. Within the shorter wavelength region we identify two additional sets of poorly resolved resonances which we associate with a f...

  • Resonance enhanced Multiphoton Ionization of the P2 radical
    The Journal of Chemical Physics, 1994
    Co-Authors: Jd Howe, Michael N. R. Ashfold, Jeffrey W. Hudgens
    Abstract:

    P2 radicals have been detected using resonance‐enhanced Multiphoton Ionization (REMPI) spectroscopy via the C 1∑+u–X 1∑+g transition. The simple structure of the origin band of this transition, which is free from significant perturbations, is amenable to straightforward simulation and thus provides an excellent route both for the detection and the characterization of ground state P2 radicals.

  • Detection and characterization of gas‐phase GaCl using resonance enhanced Multiphoton Ionization
    The Journal of Chemical Physics, 1994
    Co-Authors: David V. Dearden, Russell D. Johnson, Jeffrey W. Hudgens
    Abstract:

    We report resonance enhanced Multiphoton Ionization (REMPI) spectra of gas‐phase gallium monochloride (GaCl) produced with laser light tuned between 330 and 430 nm. The spectra originate from one, two, and three photon resonances with electronic states that reside between 29 500 and 80 000 cm−1. We have assigned five Rydberg series comprised of 20 new electronic states. Each state exhibits a short vibrational progression. A least‐squares fit of the unperturbed Rydberg state origins yields the adiabatic Ionization potential, IPa(GaCl)=80 540±10 cm−1. We have also identified bands that originate from one‐photon resonances with the previously known a 3Π state. We conservatively estimate the REMPI detection sensitivity for GaCl to be 109 molecules cm−3 (laser pulse)−1.

  • Spectra of GaCl and InCl by resonance enhanced Multiphoton Ionization spectroscopy
    1993
    Co-Authors: R.d. Johnson, D. V. Dearden, Jeffrey W. Hudgens
    Abstract:

    The authors report resonance enhanced Multiphoton Ionization spectra of gas-phase monochloride (GaCl) between 330 and 430 nm, and indium monochloride (InCl) from 330 to 500 nm. The spectra originate from one, two and three photon resonances with electronic states that reside between 27000 and 80000 cm{sup {minus}1}. The predominant peaks for both species consist of an np{pi} Rydberg series. For GaCl the authors have observed four Rydberg series including twenty new origins. For GaCl a least squares fit of the unperturbed Rydberg state origins yields an Ionization potential of 80541 {+-} 10 cm{sup {minus}1}. The authors conservatively estimate the REMPI detection sensitivity for GaCl to be 10{sup 9} molecules-cm{sup {minus}3}-(laser pulse){sup {minus}1}. For InCl the authors identify sixteen new Rydberg state origins and extrapolate to get an Ionization potential of 77463 {+-} 28 cm{sup {minus}1}.

Kazutaka G. Nakamura - One of the best experts on this subject based on the ideXlab platform.