Étude des bandes infrarouges en résonance 2ν2, ν2 + ν5, , , 2ν3 + ν5 et 4ν3 du chlorure de méthyle

1982 ◽  
Vol 60 (6) ◽  
pp. 825-843 ◽  
Author(s):  
Najath Binsari-Zizi ◽  
Claude Alamichel ◽  
Guy Guelachvili
Keyword(s):  
Fourier Transform ◽  
Standard Deviation ◽  
High Resolution ◽  
Least Squares ◽  
Methyl Chloride ◽  
Coupling Model ◽  
Fermi Resonance ◽  
Simplified Model ◽  
Interaction Scheme ◽  
Very High

The spectrum of methyl chloride has been analyzed between 2650 and 2950 cm−1 from Fourier transform recordings obtained with a very high resolution. More than 3000 lines of CH335Cl and more than 1500 lines of CH337Cl, most of them belonging to ν2 + ν5 and [Formula: see text], have been assigned: the 2ν2, [Formula: see text], 4ν3 and 2ν3 + ν5 bands are very weak and only appear when there are level crossings. The main interaction is the Coriolis resonance between the ν2 and ν5 modes, which links the rovibrational levels six by six. The Fermi resonance between [Formula: see text] and ν1, whose existence has just been shown, does not seem to have important consequences. Numerous other resonances, particularly making the 4ν3 and 2ν3 + ν5 bands visible, must be added to the basic coupling model; they make the general interaction scheme extremely complex. A least squares calculation, according to a simplified model, has given a standard deviation of 0.029 cm−1 over 784 lines of CH337Cl, from which crossings and locally perturbed subbands were excluded.

Analysis of the high resolution spectrum of the ν2 and ν5 absorption bands of methyl chloride

1984 ◽  
Vol 62 (3) ◽  
pp. 247-253 ◽  
Author(s):  
M. Morillon-Chapey ◽  
G. Guelachvili ◽  
Per Jensen
Keyword(s):  
Standard Deviation ◽  
High Resolution ◽  
Infrared Spectrum ◽  
Least Squares ◽  
Methyl Chloride ◽  
High Resolution Spectrum ◽  
Vibrational States ◽  
Absorption Bands ◽  
Least Squares Fit

The infrared spectrum of methyl chloride CH3Cl between 1280 and 1650 cm−1 has been recorded at high resolution (0.005 cm−1). The Coriolis interactions between ν2(A1) and ν5(E) and between 2ν3(A1) and ν5 have been investigated through a least squares fit to the transitions observed for CH335Cl. Ten parameters for the three upper vibrational states and three interaction constants have been determined, reproducing the 1200 observed wavenumbers with a standard deviation of 0.002 cm−1. An accidental resonance of the type l(ΔK = 2, Δl = −1) between ν2 and ν5 was found to be present in the spectrum.

High-Resolution Infrared Spectrum of Diazirine, H2CN2. Rovibrational Analysis of the Methylene Deformation Band

1988 ◽  
Vol 43 (4) ◽  
pp. 331-337 ◽  
Author(s):  
A. Gambi ◽  
A. Baldacci ◽  
S. Giorgianni
Keyword(s):  
Fourier Transform ◽  
High Resolution ◽  
Infrared Spectrum ◽  
Least Squares ◽  
Deformation Band ◽  
Fourier Transform Spectrometer ◽  
Centrifugal Distortion ◽  
Molecular Constants ◽  
Centrifugal Distortion Constants

Abstract The infrared spectrum of diazirine has been recorded at Doppler resolution with a high informa­tion Fourier transform spectrometer. The ν3 fundamental has been reinvestigated and the overall assignment of the rovibrational transitions has been carried out. From the least-squares analysis a more accurate set of molecular constants including the sextic centrifugal distortion constants has been determined for the level υ3 = 1 and will be reported here. The higher resolution achieved here allowed the assignment of weaker lines and many Q branch transitions. Moreover many blended lines have now been resolved and could be properly assigned.

Intensités des raies d'absorption des bandes perturbées ν4 et 3ν6 de 12CH335Cl

1982 ◽  
Vol 60 (9) ◽  
pp. 1328-1333 ◽  
Author(s):  
M. Dang-Nhu ◽  
M. Morillon-Chapey ◽  
G. Graner ◽  
G. Guelachvili
Keyword(s):  
Fourier Transform ◽  
High Resolution ◽  
Methyl Chloride ◽  
Intensity Parameters ◽  
Significant Intensity

Strengths of individual lines of the ν4 and 3ν6 bands of methyl chloride at 3.3 μm have been measured using a high resolution Fourier transform interferometer. From these measurements we were able to deduce two significant intensity parameters, namely the unperturbed band strength of the ν4 band, [Formula: see text] at 296.35 K and the coefficient β1 = −0.0018 ± 0.0009 of the Herman–Wallis term F = [1 + ε(ν4, J, K, J + ΔJ, K + ΔK)]2 = (1 + β1m + … )2

Vibration–rotation spectra of deuterated nitrous acid, DONO

1984 ◽  
Vol 62 (12) ◽  
pp. 1300-1305 ◽  
Author(s):  
L. O. Halonen ◽  
C. M. Deeley ◽  
I. M. Mills ◽  
V.-M. Horneman
Keyword(s):  
Fourier Transform ◽  
Standard Deviation ◽  
High Resolution ◽  
Infrared Spectra ◽  
Spectral Resolution ◽  
Nitrous Acid ◽  
Fourier Transform Infrared ◽  
Asymmetric Top ◽  
Vibration Rotation ◽  
Better Than

High-resolution Fourier transform infrared spectra have been recorded and analyzed for the ν3, ν4, ν5, and ν6 fundamental bands of trans-DONO, and for the ν4 fundamental of cis-DONO. The spectral resolution was better than 0.01 cm−1, and the bands have been fitted using an asymmetric top Hamiltonian with a standard deviation of around 0.0006 cm−1.

Vibration–rotation spectra of nitrous acid, HONO

1985 ◽  
Vol 63 (7) ◽  
pp. 962-965 ◽  
Author(s):  
C. M. Deeley ◽  
I. M. Mills ◽  
L. O. Halonen ◽  
J. Kauppinen
Keyword(s):  
Fourier Transform ◽  
Excited State ◽  
Standard Deviation ◽  
High Resolution ◽  
Infrared Spectra ◽  
Ground State ◽  
Nitrous Acid ◽  
Vibration Rotation ◽  
Line Positions ◽  
Better Than

High-resolution Fourier-transform infrared spectra have been recorded and analyzed for the ν4 ν5, and ν6 fundamental bands of trans-HONO, and for the ν4 fundamental of cis-HONO. The spectral resolution was better than 0.01 cm−1, and the rotational structure has been analyzed to give improved ground-state and excited-state rotational constants, with a standard deviation of the fit to the observed line positions of around 0.0006 cm−1. Two Coriolis interactions have been analyzed between the ν5 and ν6 bands of trans-HONO.

Study of the ν1 + ν3 and ν1 + ν6 infrared bands of methyl chloride

1981 ◽  
Vol 59 (8) ◽  
pp. 994-1008 ◽  
Author(s):  
Najate Bensari-Zizi ◽  
Claude Alamichel ◽  
Guy Guelachvili
Keyword(s):  
Least Squares ◽  
Methyl Chloride ◽  
Rotational Structure ◽  
Fermi Resonance ◽  
Molecular Constants ◽  
Isotopic Species ◽  
Expected Values ◽  
Standard Deviations

The ν1 + ν3 and ν1 + ν6 bands have been recorded with a resolution of 0.0075 cm−1 and about 2000 lines have been assigned. Classical least squares calculations (without resonance) have given standard deviations between 0.005 and 0.008 cm−1 for both bands and both isotopic species. As the molecular constants thus obtained are quite close to the expected values, the perturbations caused by a possible Fermi resonance are not really noticeable on the rotational structure.

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