First experimental observation of far-infrared translational absorption in He–Ne mixtures

1986 ◽  
Vol 64 (7) ◽  
pp. 822-825 ◽  
Author(s):  
Ph. Marteau ◽  
J. Obriot ◽  
F. Fondere
Keyword(s):  
Experimental Observation ◽  
Total Pressure ◽  
Far Infrared ◽  
Absorption Profile ◽  
Spectral Moments ◽  
Induced Absorption ◽  
First Time ◽  
Good Agreement

Collision-induced absorption in He–Ne mixtures has been observed for the first time, in a path of 1.25 m at a total pressure of 1500 bar and a temperature of 77 K. The measured zeroth and second spectral moments are in good agreement with the calculated ones. Some details of the absorption profile are also discussed.

The quadrupole moment of cyanogen: a comparative study of collision-induced absorption in gaseous C2N2, CO2, and mixtures with argon

1986 ◽  
Vol 64 (11) ◽  
pp. 1475-1481 ◽  
Author(s):  
I. R. Dagg ◽  
A. Anderson ◽  
S. Yan ◽  
W. Smith ◽  
C. G. Joslin ◽  
...  
Keyword(s):  
Quadrupole Moment ◽  
Spectral Region ◽  
Gaseous Mixture ◽  
Far Infrared ◽  
Spectral Moments ◽  
A Value ◽  
Large Anisotropy ◽  
Experimental Values ◽  
Microwave Techniques ◽  
Good Agreement

The collision-induced spectra of C2N2 gas and a gaseous mixture of C2N2 and Ar at 298 K have been obtained in the spectral region below 120 cm−1 using far-infrared laser and microwave techniques as well as a Fourier-transform spectrometer. In addition, the collision-induced spectra of a gaseous mixture of CO2 and Ar are reported at temperatures of 233 and 298 K in the spectral region below 230 cm−1. The theoretical values for the spectral moments α1 and γ1 for CO2 are much smaller than the experimental values, as expected for a molecule with a relatively large quadrupole moment. However, for CO2–Ar mixtures, the agreement between the theoretically and experimentally determined spectral moments is relatively good, resulting in a value of 4.6 B for the quadrupole moment of CO2 instead of the generally accepted value of 4.3 B. The quadrupole moment of C2N2 is estimated to be 6.2 ± 0.4 B from our data and the theory for the spectral moments, if a correction is made for an overestimate of the quadrupole moment similar to that obtained for the CO2–Ar mixture. This value is considerably smaller than a previously reported calculated result of 9.0 B. Line-shape expressions based on information theory (IT6) do not yield good agreement with experiment, a result that is attributed to the large anisotropy of the molecules.

Collision-induced absorption in gaseous mixtures of nitrogen and methane

1986 ◽  
Vol 64 (11) ◽  
pp. 1467-1474 ◽  
Author(s):  
I. R. Dagg ◽  
A. Anderson ◽  
S. Yan ◽  
W. Smith ◽  
C. G. Joslin ◽  
...  
Keyword(s):  
Far Infrared ◽  
Frequency Region ◽  
Theoretical Development ◽  
Gaseous Mixtures ◽  
Induced Absorption ◽  
Rotational Spectra ◽  
Theoretical Line ◽  
Microwave Techniques ◽  
Lower Frequency Region ◽  
Good Agreement

The collision-induced absorption spectra of nitrogen–methane gas mixtures have been measured in the spectral region below 400 cm−1 at four temperatures, namely, 212, 179, 149, and 126 K. The measurements have involved the use of Fourier-transform infrared and microwave techniques as well as a far-infrared laser operating at 84.2 and at 15.1 cm−1. These are compared with a theoretical line shape obtained from a convolution of free rotational spectra and a translational component as determined from information theory. The calculated spectra show good agreement with the experimental results only in the lower frequency region. An important feature of the theoretical development is that no adjustable parameters need be introduced.

Collision-induced absorption in a gaseous mixture of nitrogen and argon

1986 ◽  
Vol 64 (1) ◽  
pp. 7-15 ◽  
Author(s):  
I. R. Dagg ◽  
A. Anderson ◽  
S. Yan ◽  
W. Smith ◽  
C. G. Joslin ◽  
...  
Keyword(s):  
Laser System ◽  
Gaseous Mixture ◽  
Far Infrared ◽  
Theoretical Development ◽  
Induced Absorption ◽  
Theoretical Line ◽  
Microwave Techniques ◽  
Rotation Spectrum ◽  
System Operating ◽  
Good Agreement

The collision-induced absorption spectrum of a nitrogen–argon gas mixture is treated theoretically and the theory is applied to results obtained by us in the spectral region below 360 cm−1 at four temperatures, namely, 126, 149, 179, and 212 K. The measurements have involved the use of Fourier transform infrared and microwave techniques as well as a far-infrared laser system operating at 84.2 and 15.1 cm−1. The theoretical line shape is obtained from a convolution of a free rotation spectrum and a translational component. The spectra calculated from either information theory alone or combined with Mori theory both show good agreement with experimental results, especially above 30 cm−1. An important feature of the theoretical development is that no adjustable parameters need to be introduced.

Collision-induced absorption in ethylene in the microwave and far-infrared regions

1981 ◽  
Vol 59 (1) ◽  
pp. 57-65 ◽  
Author(s):  
I. R. Dagg ◽  
L. A. A. Read ◽  
B. Andrews
Keyword(s):  
Fourier Transform ◽  
Far Infrared ◽  
Microwave Cavity ◽  
Fourier Transform Spectrometer ◽  
Density Range ◽  
Spectral Moments ◽  
Induced Absorption ◽  
Hcn Laser

The collision-induced rotation–translation spectrum of gaseous ethylene has been measured at 295 K over a density range from 3.7 to 23.9 amagat in the 40–360 cm−1 region and at densities up to 50 amagat at 2.3 cm−1 and at 29.6 cm−1. The measurements were made using a Fourier transform spectrometer, an HCN laser, and a microwave cavity technique. Two spectral moments of the observed spectrum have been determined and used in a recently developed theory to provide values for the components of the quadrupole tensor of ethylene: Qxx = −3.54 × 10−26, Qyy = 1.77 × 10−26, Qzz = 1.77 × 10−26 esu. These values are compared with those obtained by other workers using different methods. The z direction is along the C–C axis, the y direction is in the plane of the molecule, and the x axis is perpendicular to the plane of the molecule.

Multicanonical Molecular Dynamics Simulation Study of the Liquid-Solid and Solid-Solid Transitions in Lennard-Jones Clusters

2011 ◽  
Author(s):  
Toshihiro Kaneko ◽  
Kenji Yasuoka ◽  
Ayori Mitsutake ◽  
Xiao Cheng Zeng
Keyword(s):  
Molecular Dynamics ◽  
Heat Capacity ◽  
Transition Temperature ◽  
Peak Position ◽  
Temperature Curve ◽  
Dynamics Simulation ◽  
Lennard Jones ◽  
Dynamics Simulations ◽  
First Time ◽  
Good Agreement

Multicanonical molecular dynamics simulations are applied, for the first time, to study the liquid-solid and solid-solid transitions in Lennard-Jones (LJ) clusters. The transition temperatures are estimated based on the peak position in the heat capacity versus temperature curve. For LJ31, LJ58 and LJ98, our results on the solid-solid transition temperature are in good agreement with previous ones. For LJ309, the predicted liquid-solid transition temperature is also in agreement with previous result.

Darstellung, Schwingungsspektren und Normalkoordinatenanalyse von Chloro-Bromo-Rhodaten(III) / Preparation, Vibration Spectra and Normal Coordinate Analysis of Chloro-Bromo-Rhodates(III)

1989 ◽  
Vol 44 (10) ◽  
pp. 1221-1227 ◽  
Author(s):  
W. Preetz ◽  
W. Kuhr
Keyword(s):  
Exchange Chromatography ◽  
Trans Isomers ◽  
Normal Coordinate ◽  
Valence Force ◽  
Trans Influence ◽  
Diethylaminoethyl Cellulose ◽  
Point Groups ◽  
First Time ◽  
Ir And Raman ◽  
Good Agreement

The mixed chloro-bromo-rhodates(III) [RhClnBr6-n]3-, n = 1-5, have been separated for the first time by ion exchange chromatography on diethylaminoethyl-cellulose. Due to the stronger trans-effect of Br, as compared with Cl, on treatment of [RhBr6]3- with conc. HCl nearly pure cis/fac-isomers for n = 2, 3, 4 are formed. The reaction of [RhCl6]3- with conc. HBr yields mixtures of the cis/trans-isomers for n = 2, 4, which cannot be separated, but mer-[RhCl3Br3]3 is formed stereospecifically. The IR and Raman spectra of all isolated mixed ligand complexes are completely assigned according to point groups Oh, D3d, C4v, C3v and C2v, supported by normal coordinate analyses based on a general valence force field. The good agreement of calculated and observed frequencies confirms the assignments. Due to the stronger trans-influence of Br as compared to Cl, in all asymmetric Cl—Rh—Br axes the Rh—Br bonds are strengthened and the Rh—Cl bonds are weakened, indicated by valence force constants for Rh—Br approximately 14% higher, for Rh—Cl 10% lower, as compared with the values calculated for symmetric Br—Rh—Br and Cl—Rh—Cl axes, respectively.

Dose-window dependence on Si crystal orientation in separation by implanted oxygen substrate formation

2004 ◽  
Vol 19 (12) ◽  
pp. 3607-3613 ◽  
Author(s):  
H. Iikawa ◽  
M. Nakao ◽  
K. Izumi
Keyword(s):  
Experimental Data ◽  
Numerical Analysis ◽  
Crystal Orientation ◽  
Oxygen Ion ◽  
The Difference ◽  
First Time ◽  
Good Agreement

Separation by implemented oxygen (SIMOX)(111) substrates have been formed by oxygen-ion (16O+) implantation into Si(111), showing that a so-called “dose-window” at 16O+-implantation into Si differs from Si(100) to Si(111). In SIMOX(100), an oxygen dose of 4 × 1017/cm2 into Si(100) is widely recognized as the dose-window when the acceleration energy is 180 keV. For the first time, our work shows that an oxygen dose of 5 × 1017/cm2 into Si(111) is the dose-window for the formation of SIMOX(111) substrates when the acceleration energy is 180 keV. The difference between dose-windows is caused by anisotropy of the crystal orientation during growth of the faceted buried SiO2. We also numerically analyzed the data at different oxidation velocities for each facet of the polyhedral SiO2 islands. Numerical analysis results show good agreement with the experimental data.

In-Plane Force Effect of Reinforced Concrete Beam with Elastic Supports

2011 ◽  
Vol 287-290 ◽  
pp. 1896-1901
Author(s):  
Zhi Kun Guo ◽  
Wan Xiang Chen ◽  
Qi Fan Wang ◽  
Yu Huang ◽  
Chao Pu Li ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Concrete Beam ◽  
Reinforced Concrete Beam ◽  
Reinforced Concrete Beams ◽  
Nonlinear Characteristics ◽  
Elastic Supports ◽  
Calculation Results ◽  
Basic Equations ◽  
First Time ◽  
Good Agreement

The bearing capacities of one-way reinforced concrete beams with elastic supports are investigated in this paper. According to the nonlinear characteristics of the beams, the basic equations based on plastic theory of concrete are derived by considering the in-plane force effects that aroused by the constraints of supports when the beams deforming. It is indicated that the calculation results are in good agreement with experimental datum, and the influences of different supports on the bearing capacities of the beams are quantitatively given for the first time.

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