Further Analyses of Infrared 1Π → 1Σ Bands of 89Y127I: New Spectroscopic Data on States up to υ"=7 and υ'=4

This paper deals with the extension of a recent study of the infrared 1Π → 1Σ emission system of the YI molecule (1). Thanks to the extreme regularity of the structure, rotational analyses can be completed for the previous 3-1, 2-0, 1-0, 0-0 and 0-1 bands and extended to 11 more bands detected step by step from their synthetic spectra (owing to the extremely dense structure). A unique and consistent set of accurate rotational constants is derived for both states, up to the levels υ" = 7 and υ' = 4, from the reduction of 5772 line wavenumbers in the bands 3-1, 2-0, 1-0, 0-0. 0-1. 0-2, 1-3, 2-4, 2-5, 3-6 and 4-7, the υ-connected bands being fitted simultaneously. The 57 estimated constants allow to reproduce the observed spectra with typical weighted rms errors between 4 and 5 mK. When using these constants to generate the bands 2-1, 1-2, 3-3, 1-4 and 3-5, ~1300 lines can be picked out whose experimental positions relatively to the predicted ones correspond to quite equivalent rms errors with nearly normal distributions of the residuals, therefore ensuring the reliability of the analysis. Molecular constants at equilibrium are derived; improvments are significant, particularly for vibration. Franck-Condon factors and r-centroïds appropriate to RKR potential curves are given. The observed bands correspond to those which are predicted to be the strongest ones in each υ'-progression.

Download Full-text

Low-lying electronic states of CuBr

Canadian Journal of Physics ◽

10.1139/p00-107 ◽

2001 ◽

Vol 79 (2-3) ◽

pp. 299-343 ◽

Cited By ~ 5

Author(s):

T Hirao ◽

P F Bernath

Keyword(s):

Fourier Transform ◽

Electronic States ◽

Buffer Gas ◽

Fourier Transform Spectrometer ◽

Molecular Constants ◽

Expansion Formula ◽

Condon Factors ◽

Mass Dependent ◽

Franck Condon ◽

Potential Curves

The A1Π X1Σ+ and B1Σ+ X1Σ+ transitions of copper monobromide, CuBr, were recorded with a Fourier transform spectrometer. The emission was generated by using a hollow cathode discharge of Ar buffer gas and a mixture of Cu and CuBr powders. The mass-dependent Dunham expansion formula was used to obtain improved molecular constants for the ground, A and B states. These molecular constants provided RKR potential curves and FranckCondon factors for the AX and BX transitions.PACS No. 35.80 transitions. PACS No. 35.80

Download Full-text

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

Canadian Journal of Physics ◽

10.1139/p73-220 ◽

1973 ◽

Vol 51 (15) ◽

pp. 1664-1677 ◽

Cited By ~ 40

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.

Download Full-text

The spectroscopy of H2CS. 1. CS stretch potential curves for singlet states of planar H2CS, obtained by ab initio multireference CI methods

Canadian Journal of Physics ◽

10.1139/p95-004 ◽

1995 ◽

Vol 73 (1-2) ◽

pp. 18-34 ◽

Cited By ~ 12

Author(s):

M. R. J. Hachey ◽

F. Grein

Keyword(s):

Dipole Moments ◽

Oscillator Strengths ◽

Excitation Energies ◽

Valence States ◽

Singlet States ◽

Symmetry Species ◽

Condon Factors ◽

Combination Modes ◽

Franck Condon ◽

Potential Curves

For planar H2CS, (C2ν), the CS stretch potential curves were obtained for the four to six lowest singlet states of each symmetry species by using multireference CI methods. Included were the (n, 4s), (n, 4p), (n, 3d), (π, 4s), and (π, 4p) Rydberg as well as the (n, π*), (π, π*), (σ, π*), (n, σ*), (n0, π*2), and (nπ, π*2) valence states. Vertical and adiabatic excitation energies, equilibrium CS distances, vibrational frequencies for the CS stretching mode, dipole moments, oscillator strengths, and Franck–Condon factors were evaluated and found to be in good agreement with known experimental data. The role of the 1(π, π*) state that diabatically crosses all 1A1 states, including the n2 ground-state configuration, causing many interactions with other states, has been given special attention. The following reassignments and predictions are of interest. (i) A switch of Ẽ and [Formula: see text], with 1A1(n, 4py) corresponding to the Ẽ bands and 1B2(n, 4pz) corresponding to the [Formula: see text] bands is suggested, based on the energetic ordering. (ii) Because of strong Franck–Condon factors, hot bands are suggested to play an important role in the analysis of the CS stretch progression of [Formula: see text]. (iii) The [Formula: see text] system, only studied in low resolution, is predicted to have high intensity and be perturbed due to the crossing of (π, π*) with (n, 4py) in the vertical region. The CS stretch bands should be observable. (iv) Observed combination modes in the [Formula: see text] system may be due to vibronic mixing of (π, π*) with (σ, π*).

Download Full-text

Calculating Franck Condon Factor and Potential Curves for X2Σ+-A2Π System of BeBr Molecule

International Letters of Chemistry Physics and Astronomy ◽

10.18052/www.scipress.com/ilcpa.52.5 ◽

2015 ◽

Vol 52 ◽

pp. 5-10

Author(s):

Adil Nameh Ayaash

Keyword(s):

Excited State ◽

Potential Function ◽

Dissociation Energy ◽

Ground State ◽

Spectroscopic Properties ◽

Spectroscopic Constants ◽

Condon Factor ◽

Condon Factors ◽

Franck Condon ◽

Potential Curves

The present work concerns by study of spectroscopic properties for Beryllium monobromide BeBr. Franck Condon Factor of BeBr molecule had been calculated theoretically for ground state X2Σ+ and excited state A2Π by special integrals by depending on spectroscopic constants for this molecule. The Dissociation energy and potential curves of this molecule is studied in this work by using Hua potential function, the results of potential curves and Franck Condon Factors converge with other researchers results.

Download Full-text

Investigations of metal ion – rare gas pairs by optical spectroscopy: High resolution analysis of the A2Πr–X2Σ+ system of BeAr+

Canadian Journal of Physics ◽

10.1139/p76-182 ◽

1976 ◽

Vol 54 (15) ◽

pp. 1535-1544 ◽

Cited By ~ 16

Author(s):

K. V. Subbaram ◽

J. A. Coxon ◽

W. E. Jones

Keyword(s):

High Resolution ◽

Metal Ion ◽

Valence Electron ◽

Rare Gas ◽

Electron Systems ◽

Molecular Constants ◽

High Resolution Analysis ◽

Condon Factors ◽

Resolution Analysis ◽

Franck Condon

Rotational analyses have been performed for the 1–0, 0–0, 0–1, 0–2, 0–3, and 0–4 bands of the A2Πr–X2Σ+ system of BeAr+ near 4000 Å. Molecular constants have been obtained by direct least squares fits of the line frequencies to model Hamiltonians. The Λ-type doubling in the A state is compared with that found for other nine valence-electron systems. RKR curves are calculated for both states, and provide an estimate of Dc″ = 4100 ± 200 cm−1 for the X2Σ+ state. Franck–Condon factors and r-centroids for the transition are also reported.

Download Full-text

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

Journal of the Serbian Chemical Society ◽

10.2298/jsc090608035a ◽

2010 ◽

Vol 75 (5) ◽

pp. 659-667 ◽

Cited By ~ 2

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.

Download Full-text