Sample−Sample and Wavenumber−Wavenumber Two-Dimensional Correlation Analyses of Attenuated Total Reflection Infrared Spectra of Polycondensation Reaction of Bis(Hydroxyethyl terephthalate)

2001 ◽  
Vol 73 (21) ◽  
pp. 5184-5190 ◽  
Author(s):  
Slobodan Šašić ◽  
Toru Amari ◽  
Yukihiro Ozaki
Keyword(s):  
Infrared Spectra ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Two Dimensional ◽  
Polycondensation Reaction ◽  
Correlation Analyses

Two-Dimensional Attenuated Total Reflection Infrared and Near-Infrared Correlation Study of the Structure of Butyl Alcohol/Water Mixtures

2007 ◽  
Vol 61 (9) ◽  
pp. 928-934 ◽  
Author(s):  
Dagmara Wojtków ◽  
Mirosław A. Czarnecki
Keyword(s):  
Near Infrared ◽  
Correlation Study ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Effect Of Temperature ◽  
Two Dimensional ◽  
Experimental Conditions ◽  
Oh Groups ◽  
Alcohol Water ◽  
Anharmonicity Constants

The effect of temperature on attenuated total reflection infrared (ATR-IR) and near-infrared (NIR) transmission spectra of pure butan-1-ol, butan-2-ol, 2-methyl-propan-1-ol, 2-methyl-propan-2-ol, and mixtures with a small water content (XH2O ≤ 0.1) have been examined. The spectra were analyzed using a two-dimensional (2D) correlation approach. Two kinds of correlation analysis were performed: IR–IR and NIR–NIR homo-correlation and IR–NIR hetero-correlation. Our results reveal that the addition of small to moderate amounts of water does not destroy the structure of alcohol. The presence of water stabilizes the structure of alcohols and this effect is more evident for sec-butanol and tert-butanol. The ATR-IR spectra provide information on the most associated species, whereas absorption of the smaller associates and the free OH group is hardly seen. On the contrary, in the NIR spectra the absorption of the free OH groups dominates. The ability of resolution enhancement in the hetero-correlation asynchronous spectra is reduced as compared to that in the homo-correlation spectra. On the other hand, peaks may appear in the hetero-correlation synchronous spectra that are not observed in the homo-correlation contour plots. The positions of the synchronous peaks were used for evaluation of anharmonicity constants. These values for the free OH group do not depend on the experimental conditions. In contrast, the anharmonicity constants for the bonded OH groups determined from the spectra of pure alcohols may significantly differ from those obtained from diluted solutions.

Polarized Infrared Attenuated Total Reflection Spectra of Powders

1984 ◽  
Vol 38 (1) ◽  
pp. 29-31 ◽  
Author(s):  
Angelo J. Barbetta
Keyword(s):  
Infrared Spectra ◽  
Amorphous Polymer ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Experimental Results ◽  
Reflection Spectra ◽  
Relative Absorption ◽  
Theoretical Predictions ◽  
Polarization Spectra ◽  
Perpendicular Polarization

Attenuated Total Reflection infrared spectra were obtained for rough and spheroidal powders made from an amorphous polymer. The spectra were recorded with a polarizer to obtain both parallel and perpendicular components of the spectra separately. The results were compared to both theoretical predictions and experimental results for the same material examined as a film. It was found that the relative absorption intensities of the two polarization spectra recorded of the film agreed well with the theory for films. However, the powdered samples showed unexpected increases in absorption intensities for the perpendicular spectra. The intensities of the absorptions for perpendicular polarization were about 45% greater than for films as measured by the ratio of relative effective thicknesses. Implications for interpretation of the spectra of powdered materials are discussed.

Transmission and Attenuated Total Reflection (ATR) Infrared Spectra of Bone and Collagen

1968 ◽  
Vol 22 (1) ◽  
pp. 23-26 ◽  
Author(s):  
H. Furedi ◽  
A. G. Walton
Keyword(s):  
Infrared Spectra ◽  
Total Reflection ◽  
Attenuated Total Reflection ◽  
Human Bone ◽  
Fair Agreement ◽  
Normal Adult ◽  
Absorption Bands ◽  
Phosphate Absorption ◽  
Adult Human ◽  
The Individual

Transmission and attenuated total reflection (ATR) spectra of collagen and normal, adult human bone have been compared with literature data and band assignments for bone spectra are given. Except for slight shifts in some absorption bands (the amide I band at 1650 cm−1 and some of the phosphate absorption bands), most frequencies of both spectra are in fair agreement with previously reported values for the individual components. An improvement in resolution of some protein bands was achieved with the ATR technique.

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