Absorption by gaseous and solid HD and solid para-H2 in the far infrared

1969 ◽  
Vol 47 (19) ◽  
pp. 2115-2123 ◽  
Author(s):  
M. Trefler ◽  
A. M. Cappel ◽  
H. P. Gush
Keyword(s):  
Absorption Spectrum ◽  
Electric Dipole ◽  
Far Infrared ◽  
Frequency Range ◽  
Significant Discrepancy ◽  
Theoretical Predictions ◽  
Rotational Transitions ◽  
Solid Hd ◽  
Calculated Intensity

The absorption spectrum of HD at 300 °K, 77.3 °K, and 4.2 °K (solid) has been measured in the frequency range of 40 to 450 cm−1. The spectrum is the sum of a collision-induced part associated with ΔJ = 2 rotational–translational transitions, and an allowed electric-dipole part associated with ΔJ = 1 rotational transitions. The intensity of the induced part of the spectrum has been compared with theoretical predictions; a significant discrepancy between the measured and calculated intensity of the S(0) line in the solid is noted. The intensity of the corresponding feature in solid parahydrogen has also been measured and a similar discrepancy exists.

Infrared Absorption by Granular Metals

1990 ◽  
Vol 195 ◽  
Author(s):  
D.B. Tanner ◽  
Y.H. Kim ◽  
C.L. Carr
Keyword(s):  
Infrared Absorption ◽  
Electric Dipole ◽  
Low Frequency ◽  
Far Infrared ◽  
Percolation Transition ◽  
Metallic Particles ◽  
Tenfold Increase ◽  
Normal Metals ◽  
Theoretical Predictions ◽  
The Individual

ABSTRACTThe infrared properties of granular metals and superconductors are qualitatively in accord with effective medium ideas, with insulating behavior below a percolation transition and metallic response above. An exception is the far-infrared absorption at low metallic concentrations, which is much stronger than theoretical predictions. Measurements of superconductors and of normal metals in different hosts suggest that this absorption is predominately electric dipole rather than the magnetic dipole (eddy current) absorption which is expected to be the dominant low-frequency loss in highly conducting particles. Measurements of clustered and non-clustered samples suggest that the strong far-infrared absorption does not arise from the clustering together of the individual metallic particles, although clustering does lead to about a tenfold increase in absorption.

Interference effects in the spectrum of HD: I. The fundamental band of pure HD

1983 ◽  
Vol 61 (12) ◽  
pp. 1648-1654 ◽  
Author(s):  
N. H. Rich ◽  
A. R. W. McKellar
Keyword(s):  
Absorption Spectrum ◽  
Dipole Moment ◽  
Phase Shift ◽  
Electric Dipole Moment ◽  
Electric Dipole ◽  
High Density ◽  
Line Profiles ◽  
Interference Effects ◽  
Permanent Electric Dipole Moment ◽  
Precise Interpretation

The absorption spectrum of the ν = 1 ← 0 band of HD has been investigated at a temperature of 77 K and for densities in the range of 15 to 140 amagat. The band consists of two components: a broad collision-induced quasi continuum arising from dipoles induced during molecular collisions; and a dipole-allowed part arising from the small permanent electric dipole moment of the free HD molecule. The interference effects which occur between these two components were studied for the dipole-allowed R1(0) and R1(1) transitions. These transitions exhibited increasingly large asymmetries and changes in intensity at high density, but their behaviours were quite different from each other. The shape of each transition could be well represented by a series of Fano line profiles, and the evolution of shape and intensity with density could be accounted for by the formulation of Herman, Tipping, and Poll. However, the precise interpretation of the phase shift parameters arising in the theory is not clear.

Adiabatische Korrektur der Born-Oppenheimer-Näherung beim GeS und GeSe / Adiabatic Correction of the Born-Oppenheimer Approximation for GeS and GeSe

1976 ◽  
Vol 31 (3-4) ◽  
pp. 374-380 ◽  
Author(s):  
W. U. Stieda ◽  
E. Tiemann ◽  
T. Törring ◽  
J. Hoeft
Keyword(s):  
Dipole Moment ◽  
High Precision ◽  
Electric Dipole Moment ◽  
Electric Dipole ◽  
Rotational Constant ◽  
Frequency Range ◽  
Rotational Spectra ◽  
Oppenheimer Approximation

Abstract The rotational spectra of GeS and GeSe were measured in the frequency range of 66 GHz to 110 GHz with high precision. The breakdown of the Born-Oppenheimer approximation was observed for the rotational constant yol. With the known molecular 37-factor and the electric dipole moment the adiabatic part of the Born-Oppenheimer correction can be extracted from the primary observa-tion on y01. The adiabatic correction is very similar in both molecules but differs from the results in the earlier measurements on PbS.

The far-infrared spectrum of hydrogen sulfide. The (000) rotational constants of , , and

1983 ◽  
Vol 61 (10) ◽  
pp. 1462-1473 ◽  
Author(s):  
J.-M. Flaud ◽  
C. Camy-Peyret ◽  
J. W. C. Johns
Keyword(s):  
Hydrogen Sulfide ◽  
Signal To Noise Ratio ◽  
Far Infrared ◽  
Infrared Region ◽  
Rotational Constants ◽  
Pure Rotation ◽  
Isotopic Species ◽  
Least Squares Fit ◽  
Rotational Transitions ◽  
Good Signal

The pure rotation spectrum of hydrogen sulfide has been recorded between 50 and 320 cm−1 with a Fourier transform spectrometer at an apodized resolution of 0.005 cm−1. This high resolution and a good signal-to-noise ratio lead to a significant improvement in the accuracy of the wavenumbers of the rotational transitions of the three isotopic species [Formula: see text], [Formula: see text], and [Formula: see text] that were observed in natural abundance. These rotational transitions, together with the available microwave data, have been included in a least squares fit leading to the determination of precise rotational constants for each isotopic species. Finally, these constants have been used to calculate precisely the absorption of natural hydrogen sulfide in the far-infrared region of the spectrum.

Elektrisches Dipolmoment von TlBr und TlJ

1971 ◽  
Vol 26 (11) ◽  
pp. 1809-1812 ◽  
Author(s):  
E. Tiemann
Keyword(s):  
Dipole Moment ◽  
Electric Dipole Moment ◽  
Electric Dipole ◽  
Vibrational State ◽  
Stark Effect ◽  
Dipole Moments ◽  
Electric Dipole Moments ◽  
Ground Vibrational State ◽  
Rotational Transitions

Stark-effect measurements on pure rotational transitions of TlBr and Til are described. The derived electric dipole moments of the most abundant isotopic molecules on the ground vibrational state are:205TL79Br : | μ0| = (4.493 ± 0.050) D , 205Tl127 I | μ 0| =(4.607 ± 0.070) D .The electric dipole moment of 205Tl19F | μ 0|=4.2282 (8) D was used as standard.

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