Energiemessung von Photoelektronen und Franck— Condon-Faktoren der Schwingungsübergänge einiger Molekülionen

1967 ◽  
Vol 22 (5) ◽  
pp. 705-710 ◽  
Author(s):  
Reimar Spohr ◽  
Ewald Von Puttkamer
Keyword(s):  
Resonance Line ◽  
Potential Method ◽  
Molecular Ions ◽  
Vibrational Structure ◽  
Vibrational Levels ◽  
Condon Factors ◽  
Experimental Values ◽  
Franck Condon

The energy of photoelectrons ejected by 21.21 eV quanta of the He resonance line is measured with a retarding potential method at a resolution of 40 meV. Vibrational structure of the molecular ions H2+, D2+, O2+, N2+, NO+, CO2+, N2O+ H20, and HC ≡ CH+ is resolved and experimental values of the FRANCK-CONDON factors for the transitions into these vibrational levels are given.

A Discussion on photoelectron spectroscopy - Franck-Condon factors and autoionization in the photoelectron spectra of diatomic molecules

1970 ◽  
Vol 268 (1184) ◽  
pp. 159-162 ◽  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Photoionization Cross Section ◽  
Resonance Wavelength ◽  
Exciting Radiation ◽  
Vibrational Structure ◽  
Photoelectron Spectra ◽  
Condon Factors ◽  
Franck Condon ◽  
Characteristic Manner ◽  
Good Agreement

Distributions of calculated Franck-Condon factors for autoionizing transitions are used to illustrate the way in which the vibrational structure of the photoelectron spectrum may be extended in a characteristic manner when the wavelength of the exciting radiation coincides with a resonance in the photoionization cross section of a diatomic gas. The calculations are found to be in good agreement with resonance wavelength photoelectron spectra from O2.

Photoautoionization structure in the halogen systems Br2, I2, BrCl, ICl, and IBr

2011 ◽  
Vol 89 (3) ◽  
pp. 289-296 ◽  
Author(s):  
Andrew J. Yencha ◽  
Devinder Kaur
Keyword(s):  
Potential Energy ◽  
Rydberg States ◽  
Molecular Ions ◽  
Spin Orbit ◽  
Shape Functions ◽  
Ionization Region ◽  
Gaussian Line Shape ◽  
Condon Factors ◽  
Franck Condon ◽  
Gaussian Line

The photoabsorption ion-yield spectra of the titled molecules have been recorded in the threshold ionization region between the two spin-orbit components of the ground states of the molecular ions. All ion-yield spectra display rather simple autoionization structure superimposed on a smoothly rising continuum in the ionization energy region. The structure was analyzed in terms of autoionizing Rydberg states and their vibrational profiles simulated using Rydberg–Klein–Rees (RKR) derived potential energy curves and calculated Franck–Condon factors using Gaussian line-shape functions. All of the structure observed is attributed to spin-orbit autoionization. There seems to be a propensity for autoionization of sσ Rydberg states in all of the interhalogen molecules studied.

Luminescence of Diatomic Molecular Ions

1971 ◽  
Vol 26 (12) ◽  
pp. 1998-2007
Author(s):  
F. J. Comes ◽  
F. Speier
Keyword(s):  
Cross Sections ◽  
Vibrational Energy ◽  
Ionic Species ◽  
Electronic Energy ◽  
Molecular Ions ◽  
Vibrational Quantum Number ◽  
Radiationless Transition ◽  
Parent Molecule ◽  
Condon Factors ◽  
Franck Condon

The ionic species N2+ B, CO+ A, CO+ B, and O2+ b have been produced by irradiation with the He I resonance line. Franck-Condon-factors both for excitation and deexcitation have been deduced from the fluorescence of the molecular ions. Most of them agree with calculated values of the Franck-Condon-factors. Measurements at different pressures ranging from 0.005 to 5 Torr lead to the deactivation cross sections for collisions with the parent molecule. N2+B also is deactivated in collisions with O2. Cross sections vary between 50 Å2 and 250 Å2 depending upon the ionic species and its vibrational quantum number. The deexcitation is described as a radiationless transition where electronic energy is transfered into vibrational energy

scholarly journals Franck-Condon factors and observed band strength distribution in the vibrational structure of the Ag2 D-X band system

2010 ◽  
Vol 75 (5) ◽  
pp. 659-667 ◽  
Author(s):  
Ankica Antic-Jovanovic ◽  
Milos Momcilovic ◽  
Vojislav Bojovic ◽  
Murtadha Khakoo ◽  
Russ Laher
Keyword(s):  
Band System ◽  
Strength Distribution ◽  
Vibrational Structure ◽  
Isotopic Effect ◽  
Molecular Constants ◽  
Band Origin ◽  
Isotopic Shifts ◽  
X Band ◽  
Condon Factors ◽  
Franck Condon

Potential curves for the X1?g+ and D1?u+ states of three diatomic silver isotopomers, 107Ag2, 107Ag109Ag and 109Ag2, were determined from the best available molecular constants by the Rydberg-Klein-Rees method. From these potentials, Franck-Condon factors and band-origin wave numbers were computed, and the reliability of the obtained values was verified by comparison with the observed band strength distribution and the measured band origin positions in a previously recorded D-X spectrum. The ratios of the Franck-Condon factors to those of corresponding isotopic bands were found to be very close to unity, revealing only a very small isotopic effect on the Franck Condon factors of Ag2 D-X bands. The isotopic shifts of the calculated band origins agree well with previously measured displacements of band heads.

Geometry Relaxations After Inner-Shell Excitations and Ionizations

2008 ◽  
Vol 73 (6-7) ◽  
pp. 771-785 ◽  
Author(s):  
Masahiro Ehara ◽  
Hiroshi Nakatsuji
Keyword(s):  
Excited States ◽  
Excitation Spectrum ◽  
Molecular Geometry ◽  
Length Change ◽  
Core Hole ◽  
Quantum Numbers ◽  
Condon Factors ◽  
Experimental Values ◽  
Franck Condon ◽  
Equilibrium Geometries

The geometry relaxations due to the inner-shell excitations and ionizations have been studied by the SAC-CI method. The characteristic molecular geometry changes were predicted for the core-hole states of CH4, NH3, H2O and HF: the calculated CH bond length change agrees well with the result simulated by the observed spectrum. The C1s excitation spectrum of CH4 was also investigated for the Rydberg states of the principal quantum numbers n = 3, 4 and 5. The potential energy curves of the dipole-allowed excited states were calculated for the totally symmetric stretching mode. The vibrational structure and Franck-Condon factors for the C1s excitation spectrum were well reproduced, which shows that the equilibrium geometries of the excited states were accurately evaluated. The geometries of the inner-shell π* excited states of N2O and CO2 were also examined. The calculated geometries of these states qualitatively agreed with the experimental values of the corresponding equivalent-core molecules.

RKR Potential, FCF and Mixing Coefficients of the A1 Σu+ and b3Πu States of Na2

1990 ◽  
Vol 45 (6) ◽  
pp. 795-798 ◽  
Author(s):  
O. Babaky ◽  
K. Hussein
Keyword(s):  
Fourier Transform ◽  
Orbit Interaction ◽  
Fourier Transform Spectrometer ◽  
Spin Orbit ◽  
Mixing Coefficients ◽  
Vibrational Levels ◽  
Condon Factors ◽  
Franck Condon ◽  
Potential Curves

AbstractA study of the spin-orbit interaction between the A1Σu+ and b3Πu states of Na2 , based on the collision-induced transitions (2) 1Σ g →A1Σu+ recorded with a high resolution Fourier transform spectrometer, had led to the determination of the deperturbed constants of the A1Σu+ and b3Πu states [1]. From these constants the Rydberg-Klein-Rees (RKR) potential curves for the A1Σu+ (0≦v≦ 15) and b3Πu (0 ≦ v ≦ 25) states and the Franck-Condon factors (FCF) within the range of vibrational levels involved in the interaction of these two states are calculated, together with the mixing coefficients for the pair (A1Σu+)v=4 - (b3Πu)v=10.

Improved Spectroscopic Data Synthesis for I2(B3ΠOu+) and Predictions of J Dependence for B(3ΠOu+)–X(1Σg+) Transition Intensities

1973 ◽  
Vol 51 (15) ◽  
pp. 1664-1677 ◽  
Author(s):  
J. David Brown ◽  
George Burns ◽  
Robert J. Le Roy
Keyword(s):  
Spectroscopic Data ◽  
Population Distribution ◽  
Intermolecular Potential ◽  
Molecular Constants ◽  
Wide Range ◽  
Vibrational Levels ◽  
Condon Factors ◽  
Vibrational Bands ◽  
Franck Condon

Some new techniques are introduced in a reanalysis of the spectroscopic data for I2(B3ΠOu+)to obtain a more complete and internally consistent set of molecular constants, and an RKR potential curve. In particular, attention is focussed on the determination of reliable high-order rotational constants (Dν, Hν, etc.) for highly excited vibrational levels. The ensuing intermolecular potential for this state is then used together with a known ground-state curve in a study of the J dependence of Franck-Condon factors for discrete B(3ΠOu+)–X(1Σg+) transitions over a wide range of ν and J. It is concluded that at the temperatures 1000–2000 °K routinely achieved in shock-tube experiments, the intensity of most vibrational bands will vary drastically as J ranges across the half-width of the thermal rotational population distribution.

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