Infrared spectral moment and molecular multipoles in collision-induced absorption

1976 ◽  
Vol 54 (5) ◽  
pp. 475-485 ◽  
Author(s):  
E. Richard Cohen
Keyword(s):  
Pair Distribution Function ◽  
Power Law Model ◽  
Multipolar Interaction ◽  
Inverse Power Law ◽  
Multicomponent Gas ◽  
Infrared Spectral ◽  
Spectral Integral ◽  
Tetrahedral Molecules ◽  
First Moment

An extension and generalization of the theory of multipolar interaction is developed which includes the effects of anisotropic polarizability, anisotropic pair distribution function, and orientational correlations. A formulation of overlap interaction is evaluated using a simple inverse power-law model. The spectral integral and the first moment of the absorption coefficient α(ω) are computed for a multicomponent gas. Anisotropic 'interference' terms couple the multipolar components so that the expressions are not simply sums over individual multipolar contributions. The theory presented here has been successfully applied in earlier published work to the determination of the multipole moments and molecular parameters of linear and tetrahedral molecules.

scholarly journals Structure determination of molecular nanocomposites by combining pair distribution function analysis and solid-state NMR

RSC Advances ◽  
2015 ◽  
Vol 5 (12) ◽  
pp. 8895-8902 ◽  
Author(s):  
E.-E. Bendeif ◽  
A. Gansmuller ◽  
K.-Y. Hsieh ◽  
S. Pillet ◽  
Th. Woike ◽  
...  
Keyword(s):  
Distribution Function ◽  
Solid State ◽  
Solid State Nmr ◽  
Pair Distribution Function ◽  
Function Analysis ◽  
Structural Characterisation ◽  
Atomic Pair Distribution Function ◽  
X Ray Scattering ◽  
Atomic Pair

Total X-ray scattering coupled to atomic pair distribution function analysis (PDF) and solid state NMR allowed the identification and structural characterisation of isolated molecules and nanocrystals of sodium nitroprusside confined in mesoporous silica.

Determination of phosphorus status in bread wheat leaves by visible and near-infrared spectral discriminant analysis

2021 ◽  
Vol 15 (01) ◽  
Author(s):  
Pamela Aracena Santos ◽  
Erdogan Esref Hakki ◽  
Sait Gezgin ◽  
Ali Topal ◽  
Mert Dedeoglu
Keyword(s):  
Discriminant Analysis ◽  
Bread Wheat ◽  
Near Infrared ◽  
Infrared Spectral ◽  
Phosphorus Status ◽  
Wheat Leaves

scholarly journals Fourier Transform Infrared Spectral Analysis of Polyisoprene of a Different Microstructure

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Dongmei Chen ◽  
Huafeng Shao ◽  
Wei Yao ◽  
Baochen Huang
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Spectral Analysis ◽  
Fourier Transform ◽  
Magnetic Resonance ◽  
Detailed Analysis ◽  
Fourier Transform Infrared ◽  
Ftir Spectra ◽  
H Nmr ◽  
Infrared Spectral

Some polyisoprene samples of different microstructure contents were studied by Fourier transform infrared (FTIR) and1H Nuclear magnetic resonance (1H NMR). On the basis of detailed analysis of FTIR spectra of polyisoprene, the shift of absorption peaks caused by microstructure content’s variation was discussed. The contents of the polyisoprene samples’ microstructure which was determined by the1H NMR was used as the standard. Through the choice, calculation, and comparison with the corresponding absorption peaks of FTIR, a method based on the results of the analysis has been developed for the determination of the microstructure contents of polyisoprene by FTIR.

Processing a Brookfield Rotational Viscometer Measurement Results in the MATLAB

2020 ◽  
Vol 834 ◽  
pp. 82-89
Author(s):  
Evgenii Igorevich Kurkin ◽  
Vladislava Olegovna Chertykovtseva ◽  
Yaroslav Vyacheslavovich Zakhvatkin
Keyword(s):  
Experimental Data ◽  
Carbon Fibers ◽  
Power Law Model ◽  
Rotational Viscometer ◽  
Measurement Results ◽  
Automatic Capture ◽  
Type Power ◽  
Short Carbon ◽  
Good Agreement

The Brookfield_to_MATLAB and ViscosityApproximation codes for processing of experiments results for determination of viscosity on a rotational Brookfield DV3T viscometer is developed in the MATLAB. The codes allow to carry out automatic capture data, to calculate the shear rate for standard spindles RV-1 ... RV-7, to sort the measurement results on temperatures, to combine the experimental data and to determine the coefficients of the Andrade type power-law model. Paper describes experiment results on determination of viscosity of the epoxy binder reinforced by short carbon fibers. The coefficients of the viscosity model are determined by the linear regression coefficients. The obtained determination coefficient shows a good agreement of the model with the experimental data. The results are used for study various contents of a mass fraction of fibers: 0%, 5%, 10%, and 15%.

scholarly journals Photothermal Determination of Absorption Coefficients in Optically Dense Fluids: Application to Oleic Acid and Water at CO Laser Wavelengths

1995 ◽  
Vol 49 (10) ◽  
pp. 1485-1489 ◽  
Author(s):  
Dane Bicanic ◽  
Mihai Chirtoc ◽  
Ileana Chirtoc ◽  
Jan Paul Favier ◽  
Per Helander
Keyword(s):  
Oleic Acid ◽  
Laser Emission ◽  
Diffusion Length ◽  
Optical Absorption Coefficient ◽  
Dead Volume ◽  
New Approach ◽  
Co Laser ◽  
Piezoelectric Detection ◽  
Infrared Spectral

Values of optical absorption coefficient β in the infrared spectral region covered by the CO laser emission were measured for homogeneous, nonscattering, and optically very dense (4 × 104 m−1 < β< 4 × 105m−1) fluids (oleic acid and water) with the use of optothermal window (OW) spectroscopy. This new approach, which combines a photothermal technique with piezoelectric detection, offers several practical advantages over conventional techniques (easy loading and cleaning, no dead volume, simple recovery of sample, etc.). A linear correlation between the optothermal signal and β exists when thermal diffusion length μ in a sample is shorter than optical penetration depth 1/β. The apparatus was calibrated with distilled water (β = 3.38 × 104 m−1 at 1781 cm−1 wave-numbers). Experimentally found β values for oleic acid and water are consistent with those measured by the spectrophotometric method. Satisfactory measurements could be performed for (0.1 < βμ < 3); the optothermal signals were large enough and far from saturation.

scholarly journals Structure determination of molecular nanocomposites by combining pair distribution function analysis and solid-state NMR

2015 ◽  
Vol 71 (a1) ◽  
pp. s383-s384
Author(s):  
Dominik Schaniel ◽  
El-Eulmi Bendeif ◽  
Axel Gansmuller ◽  
Kuan-Ying Hsieh ◽  
Sebastien Pillet ◽  
...  
Keyword(s):  
Distribution Function ◽  
Solid State ◽  
Structure Determination ◽  
Solid State Nmr ◽  
Pair Distribution Function ◽  
Function Analysis
Sign in / Sign up

Export Citation Format

Share Document