Pressure-Induced Infrared Absorption of Gaseous Hydrogen and Deuterium at Low Temperatures. III. Further Analysis of the Fundamental and First Overtone Bands of Hydrogen

1971 ◽  
Vol 49 (10) ◽  
pp. 1320-1326 ◽  
Author(s):  
A. Watanabe
Keyword(s):  
Density Dependence ◽  
Quadrupole Moment ◽  
Infrared Spectra ◽  
Infrared Absorption ◽  
Low Temperatures ◽  
Gaseous Hydrogen ◽  
Matrix Elements ◽  
Satisfactory Explanation ◽  
Satisfactory Degree ◽  
Double Transition

Pressure-induced infrared spectra of hydrogen in the fundamental region, recorded at 18, 20.4, and 24 K, have been reanalyzed making use of recently calculated theoretical matrix elements of the polarizability and the quadrupole moment of hydrogen. The analysis revealed a density dependence in the relative intensities of the single and double transition quadrupolar induced components. This density dependence was used as a correction to improve the analysis of the first overtone spectrum, obtained at 24 K with a density of 31 amagat. The observed and calculated spectra then agreed to a satisfactory degree except for a discrepancy in the intensity of the Q1(1) + Q1(J) components for which no satisfactory explanation could be given.

PRESSURE-INDUCED INFRARED ABSORPTION OF GASEOUS HYDROGEN AND DEUTERIUM AT LOW TEMPERATURES: I. THE INTEGRATED ABSORPTION COEFFICIENTS

1965 ◽  
Vol 43 (5) ◽  
pp. 818-828 ◽  
Author(s):  
A. Watanabe ◽  
H. L. Welsh
Keyword(s):  
Fine Structure ◽  
Low Temperature ◽  
Infrared Absorption ◽  
Low Temperatures ◽  
Bound States ◽  
Gaseous Hydrogen ◽  
Absorption Coefficients ◽  
Spectroscopic Evidence ◽  
Mixture Formula ◽  
Path Lengths

The pressure-induced infrared absorption of the fundamental band of hydrogen, in the pure gas and in a H2–He mixture, and of deuterium was studied in the temperature range from 18 °K to 77 °K. Path lengths up to 13.6 m at 1 atm or somewhat higher were obtained in a multiple-traversal cell cooled by liquid hydrogen or nitrogen. The binary coefficient [Formula: see text] for hydrogen shows a rise at low temperature, indicating the existence of bound states predicted by theory for the (H2)2 complex. The effect is more pronounced for deuterium. For the H2–He mixture [Formula: see text] decreases monotonically with temperature, thus showing no evidence of bound states for H2–He pairs. Fine structure at the maxima of the pressure-induced band in hydrogen and deuterium gives direct spectroscopic evidence of bound states of (H2)2 and (D2)2 complexes at low temperatures.

Theoretical study of the ν3 and ν4 Raman bands of methane in rare gas matrices

1976 ◽  
Vol 54 (13) ◽  
pp. 2154-2161 ◽  
Author(s):  
Koji Kobashi ◽  
Yosuke Kataoka ◽  
Tsunenobu Yamamoto
Keyword(s):  
Raman Scattering ◽  
Raman Spectra ◽  
Infrared Spectra ◽  
Infrared Absorption ◽  
Low Temperatures ◽  
Theoretical Study ◽  
Mutual Exclusion ◽  
Theoretical Work ◽  
Rare Gas ◽  
Vibration Rotation

Theoretical study has been carried out on the Raman spectra of the ν3 and ν4 vibration bands of methane in Ar, Kr, and Xe matrices at low temperatures. The present study is a continuation of a theoretical work by Nishiyama and Yamamoto on the infrared spectra of the same Systems. We consider the symmetry of the System under the group [Formula: see text] introducing the inversion functions to generalize Wigner's rotational functions. As a result, dual assignments are given to each vibration–rotation state. The allowed transitions of the Raman scattering are compared with those of the infrared absorption, and it is found that a kind of 'rule of mutual exclusion' holds. The relative intensities and spacings of the Raman spectra are calculated and successfully compared with experiment.

PRESSURE-INDUCED INFRARED ABSORPTION OF GASEOUS HYDROGEN AND DEUTERIUM AT LOW TEMPERATURES: II. ANALYSIS OF THE BAND PROFILES FOR HYDROGEN

1967 ◽  
Vol 45 (9) ◽  
pp. 2859-2871 ◽  
Author(s):  
A. Watanabe ◽  
H. L. Welsh
Keyword(s):  
Infrared Absorption ◽  
Low Temperatures ◽  
Theoretical Calculations ◽  
Computational Procedure ◽  
Gaseous Hydrogen ◽  
Infrared Band ◽  
Line Form ◽  
Dispersion Line ◽  
Good Agreement

Experimental profiles for the pressure-induced fundamental infrared band of hydrogen for a number of temperatures in the range 18–77 °K were analyzed by a computational procedure. Half-widths and peak intensities of 11 components, assumed to have a Boltzmann-modified dispersion line form, were obtained from the analysis. The contributions of the quadrupolar and overlap interactions to the total intensity, as well as their variation with temperature, showed good agreement with theoretical calculations on the exp–4 model.

Pyrrole Studies. I. The Infrared Spectra of 2-Monosubstituted Pyrroles

1963 ◽  
Vol 16 (1) ◽  
pp. 93 ◽  
Author(s):  
RA Jones
Keyword(s):  
Infrared Spectra ◽  
Infrared Absorption ◽  
Absorption Bands ◽  
Infrared Absorption Bands

The positions and intensities of the characteristic infrared absorption bands of the nucleus are recorded and discussed for thirty-five 2-monosubstituted pyrroles.

Infrared spectra of KH2F3 and the structure of the H2F3− ion

1967 ◽  
Vol 45 (12) ◽  
pp. 1347-1350 ◽  
Author(s):  
A. Ažman ◽  
A. Ocvirk ◽  
D. Hadži ◽  
Paul A. Giguère ◽  
Michel Schneider
Keyword(s):  
Solid State ◽  
Infrared Spectra ◽  
Infrared Absorption ◽  
Normal Coordinate Analysis ◽  
Force Constants ◽  
Hydrogen Atoms ◽  
Normal Coordinate ◽  
Bending Modes

The infrared absorption of KH2F3 and KD2F3in the solid state was measured between 4 000 and 200 cm−1 The observed bands can be assigned to the stretching and bending modes of the bent H2F3− ion. A normal coordinate analysis was carried out to determine the Urey–Bradley force constants. The results suggest that the hydrogen atoms are not exactly halfway between two fluorine atoms, contrary to the case of the HF2− ion.Les spectres infrarouges de KH2F3 et KD2F3 à l'état solide ont été mesurés entre 4 000 et 200 cm−1 afin d'identifier les vibrations fondamentales de l'anion H2F3−. Les constantes de forces de rappel selon le modèle de Urey–Bradley ont pu être déterminées par analyse des coordonnées normales. Les résultats indiquent que les atomes d'hydrogène ne sont pas exactement à mi-chemin entre deux atomes de fluor, contrairement au cas de l'ion HF2−.

scholarly journals ON THE INFRARED ABSORPTION OF WATER AND HEAVY WATER IN CONDENSED STATES

1956 ◽  
Vol 34 (6) ◽  
pp. 798-808 ◽  
Author(s):  
Paul A. Giguère ◽  
K. B. Harvey
Keyword(s):  
Thin Films ◽  
Absorption Band ◽  
Water Molecule ◽  
Air Temperature ◽  
Heavy Water ◽  
Infrared Spectra ◽  
Infrared Absorption ◽  
Silver Chloride ◽  
Strong Absorption Band ◽  
Librational Mode

The infrared spectra (from 2 to 30 μ) of thin films of H2O and D2O were measured at various temperatures between 20 ° and −180 °C. A strong absorption band due to the librational mode of the water molecule has its maximum around 710 cm.−1 in the liquid. In ice it is shifted to 800 cm.−1 at −15 °C. and 850 cm.−1 at −170 °C. The corresponding D2O bands show the normal isotope shift. Thin films of water pressed between silver chloride plates could not be crystallized even at liquid air temperature as confirmed by their spectra, which were almost identical with those of the liquid.

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