The IR spectra of 2-haloethylamines V. The intensity of the C-Cl and C-Br stretching vibration bands in Kbr disks

1973 ◽  
Vol 18 (6) ◽  
pp. 750-753
Author(s):  
L. V. Sennitskaya ◽  
B. S. Kikot' ◽  
O. M. Belokon' ◽  
Yu. A. Pentin
Keyword(s):  
Ir Spectra ◽  
Stretching Vibration

Influence of KBr conditioning on the infrared hydroxyl-stretching region of saponites

Clay Minerals ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 439-445 ◽  
Author(s):  
M. Pelletier ◽  
L. J. Michot ◽  
O. Barrès ◽  
B. Humbert ◽  
S. Petit ◽  
...  
Keyword(s):  
Ir Spectroscopy ◽  
Ir Spectra ◽  
Clay Minerals ◽  
Diffuse Reflectance ◽  
Layer Charge ◽  
Tetrahedral Sheet ◽  
Stretching Vibration ◽  
Sheet Charge

AbstractIn order to assess the influence of tetrahedral sheet charge on the hydroxyl-stretching vibration in clay minerals, a series of synthetic Na-saponites, with increasing layer charge, was studied by infrared (IR) spectroscopy. When recorded after KBr dilution either in transmission or diffuse reflectance, the IR spectra exhibit a component at ~3710 cm-1, the intensity of which increases linearly with increasing layer charge. When experiments are carried out without any dilution of the samples, this component is not observed, suggesting a Na+/K+ exchange upon mixing of the sample with KBr. The spectra obtained for K-saponite confirm this exchange. This shows that the dilution procedure can lead to serious misinterpretations of IR spectra in the OH-stretching region.

Synthesis of Chelating Surfactant and its Application in Silk Degumming

2011 ◽  
Vol 331 ◽  
pp. 245-248
Author(s):  
Yun Zhang ◽  
Xi Tao Sun ◽  
Xiang Rong Wang
Keyword(s):  
Surface Tension ◽  
Critical Micelle Concentration ◽  
Ir Spectra ◽  
Surface Activity ◽  
Stretching Vibration ◽  
Degumming Process ◽  
Degumming Agent

Ethanediyl-N-hexadecyl-tri(sodium α-glycinate) (N-hexadecyl ED3A), which belongs to the chelating surfactants, was synthesized by three-step reactions in this study. The structure of the product was characterized by IR. The surface activity and the properties of N-hexadecyl ED3A as degumming agent were investigated. The IR spectra showed the characteristic bands corresponding to the stretching vibration of C-N, -COONa, and C-H groups. The critical micelle concentration (cmc) of N-hexadecyl ED3A was 0.249mmol•L-1, and the surface tension at the cmc (γcmc) of it was 33.03mN•m-1. This revealed that the surfactant had fairly low cmc and excellent surface activity. Lower dosage of N-hexadecyl ED3A showed as good result as the conventional soap in silk degumming process, and the degumming result was also excellent without adding the chelating dispersant.

FT-IR Spectroscopic Study of 1,5-Pentanedithiol and 1,6-Hexanedithiol Adsorbed on NaA, CaA and NaY Zeolites

2005 ◽  
Vol 60 (8-9) ◽  
pp. 633-636 ◽  
Author(s):  
Nuri Öztürk ◽  
Çağrı Çırak ◽  
Semiha Bahçeli
Keyword(s):  
Infrared Spectroscopy ◽  
Ir Spectra ◽  
Spectroscopic Study ◽  
The Other ◽  
Other Hand ◽  
Liquid Phases ◽  
Stretching Vibration ◽  
Ft Ir ◽  
Ir Spectroscopic ◽  
Nay Zeolites

The adsorption of 1,5-pentanedithiol (1,5-PDT) and 1,6-hexanedithiol (1,6-HDT) in liquid phases on NaA (or 4A-type), CaA (or 5A-type) and NaY zeolites has been studied by using infrared spectroscopy. From the IR spectra it is found that the peak positions of the symmetric as well as the antisymmetric modes of the methylene (CH2) groups are observed at almost the same band values for the title dithiolates adsorbed on the A-type and NaY zeolites. On the other hand, the weak SH stretching vibration, observed for all samples, can be attributed to the sulphure atoms of 1,5-PDT and 1,6-HDT coordinatively adsorbed on cationic sites of the zeolites.

FTIR STUDY ON MOLECULAR CONTAMINATION ON SURFACE OF OPTICAL MATERIALS

2006 ◽  
Vol 20 (25n27) ◽  
pp. 3860-3865 ◽  
Author(s):  
MASAHIRO KATOH ◽  
NOBUAKI OKANO ◽  
TOSHIHIDE HORIKAWA ◽  
TAHEI TOMIDA ◽  
NOBUNARI ITOH
Keyword(s):  
Ir Spectra ◽  
Optical Materials ◽  
Functional Group ◽  
The Other ◽  
Absorption Bands ◽  
Bending Vibration ◽  
Absorption Intensity ◽  
Stretching Vibration ◽  
Optical Disks ◽  
Molecular Contaminants

The IR spectra of the molecular contaminants on surface of optical materials were measured. The optical disks used were SiO 2, BK7 ( SiO 2 70%, B 2 O 3 10%, K 2 O 8%, N 2 O 8%), CaF 2, ZnSe and Al 2 O 3. N 2, O 2, H 2 O , and CO 2 were adopted as contamination gases. IR spectra of H 2 O (2.7kPa) on BK7 at 373K showed two absorption bands ( OH stretching vibration: around 4000cm-1-3500cm-1 and OH bending vibration: around 2000cm-1-1500cm-1). The absorption intensity decreased with a decrease in temperature and a new band (around 3250cm-1) appeared at 173K. The new band was attributed to phase transition of H 2 O . These phenomena were also observed on the other three discs, except for SiO 2. IR spectra of SiO 2 showed OH stretching band (3676cm-1). The absorption intensity decreased with a decrease in temperature. But two new bands (3720cm-1 and 3620cm-1) appeared under an atmosphere of N 2 (66.5kPa), O 2 (66.5kPa), H 2 O (2.7kPa) or CO 2 (0.7 or 13.3kPa). A similar phenomenon was also observed for BK7, which has OH group. These results suggested the functional group of SiOH interacted with contamination molecules.

Fourier Transform Infrared Spectra of Calf Thymus DNA and its Reactions with the Anticancer Drug Cisplatin

1981 ◽  
Vol 35 (5) ◽  
pp. 461-465 ◽  
Author(s):  
Theophile Theophanides
Keyword(s):  
Fourier Transform ◽  
Ir Spectra ◽  
Anticancer Drug ◽  
Fourier Transform Infrared ◽  
Reaction Products ◽  
Sugar Phosphate ◽  
Platinum Drug ◽  
Absorption Region ◽  
Ribose Phosphate ◽  
Stretching Vibration

Fourier transform infrared (FT-IR) spectra of deoxyribonucleic acid (DNA) and its reaction products with the anticancer drug cis-Pt(NH3)2Cl2, cis-diamminodichloroplatinum (abbreviated cisplatin) in water and heavy water solutions or gels have been obtained and studied. The mid-IR spectra show considerable changes in the carbonyl (C=0) region and weaker, but significant perturbations in the sugar-phosphate absorption region (PO2−, OPC and COP). The carbonyl bands at 1710 and 1686 cm−1 of the control DNA in H2O and D2O, respectively, disappear and shift to lower frequencies in the spectra of cisplatin + DNA with a r = Pt/P = 0.2. Furthermore, the sugar-phosphate band at 1054 cm−1 of the C—O stretching vibration of the ribose-phosphate bond is reduced in intensity and slightly shifted to higher frequencies, indicating a reorientation of the phosphate group. In addition, the P—O stretching vibration frequency at 970 cm−1 is reduced in intensity on interaction with the drug. These changes depend to some extent on the water content in the control DNA and in the cisplatin + DNA complex. The water molecules in DNA in the presence of cisplatin reorganize themselves. The attack of the platinum drug at the N7 site of the guanine molecule in DNA exerts an effect on the DNA structure through a modification of the water average configuration and its stabilizing effect on the secondary structure.

Die Polarisation der σ-Bindungen im Azulen

1972 ◽  
Vol 27 (1) ◽  
pp. 110-128 ◽  
Author(s):  
H. Seydewitz ◽  
E.D. Schmid
Keyword(s):  
Experimental Data ◽  
Ir Spectra ◽  
Linear Function ◽  
Electron Density ◽  
Coupling Constants ◽  
Ir Absorption ◽  
Absorption Intensity ◽  
Bond Lengths ◽  
Stretching Vibration ◽  
Stretching Vibrations

Abstract On the basis of a simple MO-approach a model to interprete the IR-absorption intensity of the aromatic CH-stretching vibration is developed. Accordingly the gradient of the CH-bond moment is a linear function of the ionicity of the CH-bond.Eight azulenes, which were deuterated at various specified positions, were synthetisized and out of their IR-spectra the gradients of the CH-bond moment at all positions of azulene could be determined. From these experimental data it is concluded, that in relation to benzene the electrons of the CH-bonds in azulene are displaced towards the C-atom at positions with high and towards the H-atom at positions with low π-electron density.Such a polarisation of the CH-bonds in azulene is confirmed, although only qualitatively, by the ionicities of the CH-bonds calculated by the CNDO/2-method and is also in accordance with other experimental observations such as bond lengths and angles, C13H-coupling constants, and the frequencies of the CH-stretching vibrations.It is demonstrated that experiment and calculation fail to correlate quantitatively due to in-adequacies inherent in the CNDO/2-method.

FT-IR Spectra Of The C=O And C-H Stretching Vibration Of Lauric Acid

1989 ◽  
Author(s):  
Weng Shifu ◽  
Wu Jinguang ◽  
Xu Guangxian
Keyword(s):  
Ir Spectra ◽  
Lauric Acid ◽  
Stretching Vibration ◽  
Ft Ir

The molecular conformations of the stereoisomers of 4-methyl-5,6-benzo-2-oxo-1,3,2-dioxathiepin and of the 4,7-dimethyl derivative

1983 ◽  
Vol 61 (10) ◽  
pp. 2244-2253 ◽  
Author(s):  
A. Lachapelle ◽  
M. St-Jacques ◽  
A. C. Guimaraes ◽  
P. De Almeida
Keyword(s):  
Low Temperature ◽  
Ir Spectroscopy ◽  
Ir Spectra ◽  
Nmr Spectra ◽  
Dynamic Properties ◽  
Substituent Effects ◽  
Spectroscopy Analysis ◽  
Molecular Conformations ◽  
Methyl Group ◽  
Stretching Vibration

The conformational and dynamic properties of the stereoisomers of 4-methyl-5,6-benzo-2-oxo-1,3,2-dioxathiepin (5) and of the 4,7-dimethyl derivative (6) have been investigated by 1H and 13C dnmr methods, as well as by ir spectroscopy. Analysis of the nmr spectra at low temperature (−125 °C), together with the conformational interpretation of the stretching vibration bands of the S = O bond in the ir spectra, indicate that the most stable conformations detected for solutions in CHF2Cl are C-a (82%) and TB-t-Mec (18%) for 5a, TB-c-Mec, (96%) and TB-c-Mea, (4%) for 5b, C-a for 6a, TB-t-Mec, c-Mec, for 6b and C-e for 6c. The substituent effects of a methyl group at the benzylic position on both the conformational and dynamic properties of the seven-membered sulfite are discussed.

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