scholarly journals The IR Spectra, Molar Absorptivity, and Integrated Molar Absorptivity of the C76-D2and C84-D2:22 Isomers

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Tamara Jovanović ◽  
Đuro Koruga ◽  
Branimir Jovančićević

The FT-IR spectra of the stable C76and C84isomers of D2symmetry, isolated by the new, advanced extraction and chromatographic methods and processes, were recorded by the KBr technique, over the relevant region from 400 to 2000 cm−1, at room temperature. All the observed infrared bands are in excellent agreement with the semiempirical QCFF/PI, DFT, and TB potential calculations for these fullerenes, which is presented in this article, as the evidence of their validity. The molar absorptivityεand the integrated molar absorptivityψof their IR absorption bands were determined and reported together with the relative intensities. Excellent agreement is found between the relative intensities of the main and characteristic absorption maxima calculated fromελand from theψλvalues in adequate integration ranges. These results are significant for the identification and quantitative determination of the C76-D2and C84-D2:22 fullerenes, either in natural resources on Earth and in space or in artificially synthesized and biomaterials, electronic, optical, and biomedical devices, sensors, polymers, optical limiters, solar cells, organic field effect transistors, special lenses, diagnostic and therapeutic agents, pharmaceutical substances in biomedical engineering, and so forth.

2011 ◽  
Vol 287-290 ◽  
pp. 1666-1670 ◽  
Author(s):  
Ying Nan Cong ◽  
Ying Liu ◽  
Rui Sheng Hu

A novel and efficient method was established to investigate isobutane/2-butene alkylation. In this method FT-IR spectroscopy was used to determine the presence of the composite ion (AlCuCl5-) in the composite ionic liquid (CIL). The trimethylpentane selectivity of the composite ionic liquid for isobutane/2-butene alkylation was also estimated by monitoring the shift of IR absorption bands in the range 1636–1685 cm-1. A detailed study of the alkylation of isobutane /2-butene in CIL media has been conducted using 1-alkyl-3-methylimidazolium halide/X aluminum chloride-y cuprous (I) chloride ([CnMIM]Cl/xAlCl3-yCuCl) encompassing various alkyl groups (n=4:B, butyl-, n=6:H, hexyl-, and n=8: O, octyl-)respectively. The ionic liquids showed higher selectivities of C8 as well as the TMP/DMH ratios in alkylates. The better catalytic performance of CIL can be attributed to the presence of the composite ion in it, and the catalytic performance of the chloroaluminate ionic liquid can be indicated by the 1685 cm-1band of FT-IR spectroscopy.


2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Tamara Jovanović ◽  
Djuro Koruga ◽  
Aleksandra Mitrović ◽  
Dragomir Stamenković ◽  
Gordana Dević

The only stable isomer of the higher fullerene C76 of D2 symmetry was isolated from carbon soot by the new and advanced extraction and chromatographic methods and processes. Characterization of the isolated C76-D2 was performed by the IR(KBr) and UV/VIS method in the absorption mode. All of the experimentally observed infrared and electronic absorption bands are in excellent agreement with the theoretical calculations for this fullerene. The molar absorptivity ε and the integrated molar absorptivity Ψ of the observed entire new series of various characteristic, both deconvoluted and convoluted IR absorption bands of the C76-D2 isomer, in different integration ranges were determined. In addition, the molar extinction coefficients of its UV/VIS absorption bands were determined. The obtained novel IR and UV/VIS spectroscopic parameters are significant for the quantitative assessment of C76-D2. All the presented data are important both for its qualitative and quantitative determination, either in natural resources on Earth and in space or in artificially synthesized materials, electronic and optical devices, optical limiters, sensors, polymers, solar cells, nanophotonic lenses, diagnostic and therapeutic agents, pharmaceutical substances, for targeted drug delivery, incorporation of metal atoms, in biomedical engineering, industry, applied optical science, batteries, catalysts and so forth.


2014 ◽  
Vol 17 (2) ◽  
pp. 86-92
Author(s):  
Lam Le ◽  
Tuan Anh Luu

Among semiconducting polymers, poly(3-alkylthiophene)s have attracted great attention and generated many studies over the past few years. Among them, regioregular (head-to-tail) poly(3-hexylthiophene) (P3HT) has been especially investigated due to its superior opto-electronic properties, good solubility in the most common organic solvents, chemical and thermal stabilities and also very low toxicity. These properties enable P3HT to be significantly useful in a large variety of applications such as optical sensors, smart windows, organic field effect transistors (OFETs), electrochromic devices, and solar cells. Here, we report the synthesis of poly(3-hexylthiophene) (P3HT) and investigate the optical properties of P3HT in different solvents such as chloroform, tetrahydrofuran, toluene, ethylacetate. The structures of P3HT were confirmed by nuclear magnetic resonance (1H NMR), gel permeation chromatography (GPC), Fourier transform infrared (FT-IR).


2002 ◽  
Vol 56 (10) ◽  
pp. 1259-1267 ◽  
Author(s):  
Cyril Petibois ◽  
Georges Cazorla ◽  
André Cassaigne ◽  
Gérard Déléris

Global metabolic adaptations to physical conditioning were described in 15 subjects by FT-IR spectrometry as the method allowed determination of glucose (Glc), lactate (La), glycerol, triglycerides (TG), fatty acyl moieties (FAM), and total amino acids plasma concentrations. Subtraction of plasma FT-IR spectra obtained at resting state from the exercise spectra also allowed determination of the biomolecular response to exercise. On week 1, exercise induced a transient hypoglycemia, a lactatemia increase of 153%, a FAM depletion of 27%, and a TG concentration decrease of 28%. Protein contents increased by 2%, but these were partly catabolized for amino acid supply (+27%), suggesting an important metabolic stress during exercise. On week 3, exercise hypoglycemia had disappeared, lactate increase was diminished by 91%, TG contents were decreased by 14%, and proteins and amino acids exhibited higher absorption increases. On week 5, TG and FAM concentrations were markedly increased during exercise, protein absorption was still increased (+9%), but amino acid blood release was diminished by 81%. These results described positive adaptations to training. Furthermore, FAM concentration could be determined from plasma FT-IR spectra by using the 2996–2819 cm−1 spectral area [ νas(CH3), νas(CH2), νs(CH3), and νs(CH2) absorbance; 0.82 mMol·L−1, a.u. cm−1], as well as for amino acid concentration by using the ν(COO−) spectral area (1430–1360 cm−1; 0.062 g·L−1, a.u. × cm−1). FT-IR spectrometry was useful to determine simultaneously various plasma concentrations and most of the biomolecular changes through successive samples.


Clay Minerals ◽  
1981 ◽  
Vol 16 (4) ◽  
pp. 375-382 ◽  
Author(s):  
Jose L. Rendon ◽  
Carlos J. Serna

AbstractHematites obtained by heating goethite gave different IR absorption spectra depending on the temperature of formation. Hematites formed between 250–600°C consisted of lath-like crystals (average size 0.4 ×0.08 µm) and showed, in accordance with theoretical predictions, very similar IR spectra whose absorption bands could all be assigned to surface mode vibrations. However, significantly different IR spectra were given by hematites formed between 700–950°C, the differences being correlated with variations in the size and shape of the particles. Differences observed in the IR spectra of powder hematite do not therefore justify new names for the mineral, as have been proposed in the literature.


2020 ◽  
Vol 10 (11) ◽  
pp. 3895 ◽  
Author(s):  
Salman. S. Alharthi ◽  
Hamed. M. Al-Saidi

A simple, selective, and inexpensive spectrophotometric method is described in the present study for estimation of trace concentrations of Cu2+ in water based on its reaction with chromogenic reagent namely 4-amino-3-mercapto-6-[2-(2-thienyl)vinyl]-1,2,4-triazin-5(4H)-one (AMT). The reaction between copper(II) ions and AMT reagent gives [Cu(L)(NO3)(H2O)2]•H2O complex, where L represents AMT molecule with NH group. The formed complex exhibits a sharp, and well-defined peak at λmax = 434 nm with a molar absorptivity (ε) of 1.90 × 104 L mol−1 cm−1, and Sandell’s factor of 0.003 μg mL−2. Absorbance of the [Cu(L)(NO3)(H2O)2]•H2O follows Beer’s law over a 0.7–25 μg mL−1 range with a detection limit of 0.011 μg mL−1. Validation of the submitted method was established by estimating Cu2+ in certified reference materials and actual sea and tap water samples. The results are compared with data obtained from copper concentration measurements using ICP-OES. The chemical structure of the Cu(II)-AMT complex was fully characterized by FT-IR, SEM, EDX, TGA, and ESR techniques.


2016 ◽  
Vol 855 ◽  
pp. 47-53
Author(s):  
Ampa Jimtaisong ◽  
Nisakorn Saewan

Inclusion complex of β-cyclodextrin (β-CD) and Plai (Zingiber cassumunar) oil was prepared using a simple co-precipitation method at β-CD to Plai oil in different ratios. The inclusion complexes were characterized using Fourier transform-infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC). The FT-IR absorption bands of inclusion complex at 3600-3200 cm-1 were broader and shifted toward lower frequencies compared with that of pure β-CD (3359 cm-1). DSC of the inclusion complexes showed two endothermic peaks shifted to lower temperatures (90-100°C and 295-300°C) compared to that of β-CD. The different physicochemical characteristic could be an indication of an embedded guest molecule in the β-CD cavities in the inclusion complex preparation.


1986 ◽  
Vol 40 (7) ◽  
pp. 1068-1069 ◽  
Author(s):  
M. S. Akhter ◽  
A. R. Chughtai ◽  
D. M. Smith

2012 ◽  
Vol 260-261 ◽  
pp. 593-597
Author(s):  
Veronika Sassmanová ◽  
Zuzana Poláčková ◽  
Jaroslav Frantík ◽  
Stanislav Honus ◽  
Dagmar Juchelková

The article deals with the identification of a chemical structure of pyrolysis liquid occurring by the thermal degradation of tyre debris within the temperature interval from 500°C to 650°C and the temperature increase steps of 50°C in individual experiments and with the use of analytical methods GC/MS, FT-IR and the elementary analysis. The measured FT-IR spectra indicate the representation of functional groups included in measured samples. They could be used for the determination of basic chemical properties. There were changes in the chemical composition monitored as well as the creation of functional groups in the pyrolysis liquid on the basis of FT-IR spectra and GS/MS outcomes.


Clay Minerals ◽  
1999 ◽  
Vol 34 (2) ◽  
pp. 365-374 ◽  
Author(s):  
F. Martin ◽  
S. Petit ◽  
O. Grauby ◽  
M. P. Lavie

AbstractThe deuteration technique was used to assign unknown infrared (IR) bands of Ge-bearing talcs. Procedures to achieve partial or complete H/D replacement in synthetic Ge-bearing (Mg, Ni and Co)-talcs have been investigated. From the spectral shift of IR absorption bands in the 4000–300 cm-1 region resulting from the H-D substitution, the IR bands of vibrations of Ge-bearing talcs could be identified and synthetic Ge-bearing talcs showed significantly different IR spectra from those for Si-talcs. After deuteration of synthetic Ge-bearing talcs, the unknown bands were attributed either to hydroxyl groups or to Ge–O vibrations of the clay skeleton, and the spectra were interpreted fully.


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