Identification of Absorption Bands of Monomers and Aggregates in a Layer of Cyanine Dye and Determination of the Orientation of Molecules

Five N-p-phenyl substituted benzamidines were studied by DC and DP polarography in a wide pH range. Coulometric results show that the overall processes are four-electron reductions. Logarithmic analysis of the waves indicate that the process are irreversible. The influence of the pH on the polarographic parameters was also studied. A UV spectrophotometric study was performed in the pH range 2-13. In basic media some variations in the absorption bands were observed due to the dissociation of the amidine group. A determination of the pK values was made by deconvolution of the spectra. Correlations of both the electrochemical parameters and spectrophotometric pK values with the Hammett substituent constants were obtained.

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A III B VI PHOTOVOLTAIC RECEPTORS FOR EXPERIMENTAL DETERMINATION OF CARBON COMPOUNDS IN ATMOSPHERE

Journal of Engineering Studies and Research ◽

10.29081/jesr.v19i3.111 ◽

2016 ◽

Vol 19 (3) ◽

Author(s):

IULIANA CARAMAN ◽

IGOR EVTODIEV ◽

OXANA RACOVEŢ ◽

MARIUS STAMATE

Keyword(s):

Electric Fields ◽

Full Range ◽

Absorption Bands ◽

Gaseous State ◽

Wide Range ◽

Carbon Compounds ◽

Strong Electric Fields ◽

Qualitative Measurements ◽

Semiconductor Type

This paper examines the prospects of using semiconductor layered A III B VI type - photovoltaic cells and the photoresistors as receptors for quantitative and qualitative measurements of carbon oxides. Carbon compounds in gaseous state form absorption bands of electromagnetic radiation in a wide range of spectrum (200 ÷ 100 000) cm-1. The light absorbed or emitted in these bands at the excitations with ionizing radiation (X, γ) or strong electric fields contain direct information about the concentration of these molecules. The frequencies that correspond to maxima of these bands are characteristic parameters of absorbing molecules. Fundamental absorption bands of CO, CO 2 and NC have the edge of band at the border of ultraviolet-vacuum, while the emission bands d cover their full range of wave numbers from 45000 cm-1 to 10000 cm-1. Two types of radiation receptors from lamellar semiconductor type AIIIBVI photosensitive in this spectral range are studied.

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IR DETERMINATION OF THE ORIENTATION OF MOLECULES IN POLYCRYSTALLINE MONOLAYERS

Langmuir–Blodgett Films ◽

10.1016/b978-0-444-41901-9.50008-2 ◽

1980 ◽

pp. 13-19

Author(s):

P.A. CHOLLET

Keyword(s):

Orientation Of Molecules

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Determination of electrooptical parameters of molecules with the use of nonempirical quantum-chemical calculations of absolute intensities of absorption bands in the IR region

Journal of Applied Spectroscopy ◽

10.1007/bf02679213 ◽

1999 ◽

Vol 66 (1) ◽

pp. 15-20 ◽

Cited By ~ 1

Author(s):

L. A. Gribov ◽

D. I. Sidelov ◽

I. V. Maslov

Keyword(s):

Quantum Chemical Calculations ◽

Quantum Chemical ◽

Absorption Bands ◽

Absolute Intensities ◽

Electrooptical Parameters

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Liquid Chromatographic Determination of Primary and Secondary Amines as 8-Quinolinesulfonyl Chloride Derivatives

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/67.4.687 ◽

1984 ◽

Vol 67 (4) ◽

pp. 687-691

Author(s):

F Taylor Noggle ◽

C Randall Clark

Keyword(s):

Chromatographic Determination ◽

Secondary Amines ◽

Absorption Bands ◽

Reverse Phase ◽

Primary And Secondary Amines ◽

Liquid Chromatographic Determination ◽

Phase Liquid ◽

Liquid Chromatographic ◽

Derivatives Of

Abstract The normal phase and reverse phase liquid chromatographic properties of seven 8-quinolinesulfonyl derivatives of primary and secondary amines are examined using dual wavelength ultraviolet detection. The amines are further identified by infrared spectrophotometry with emphasis on structural elucidation based on absorption bands at characteristic wavelengths.

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Determination of phosphate anions with a near-infrared heptamethine cyanine dye in a neutral aqueous solution

Analytical Methods ◽

10.1039/c9ay00425d ◽

2019 ◽

Vol 11 (20) ◽

pp. 2677-2682 ◽

Cited By ~ 3

Author(s):

Xia Gao ◽

Jie Xu ◽

Baoxian Ye ◽

Weidong Wu ◽

Hong Zheng

Keyword(s):

Aqueous Solution ◽

Near Infrared ◽

Cyanine Dye ◽

Neutral Aqueous Solution ◽

Phosphate Anions ◽

Novel Strategy

A novel strategy was developed for the detection of phosphate anions with anionic heptamethine cyanine and Tb3+ in the NIR region.

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Applications of Infrared Methods in the Structural Examination of Synthetic Rubber

Rubber Chemistry and Technology ◽

10.5254/1.3543250 ◽

1946 ◽

Vol 19 (4) ◽

pp. 1113-1123 ◽

Cited By ~ 2

Author(s):

J. E. Field ◽

D. E. Woodford ◽

S. D. Gehman

Keyword(s):

Absorption Spectra ◽

Organic Molecules ◽

Normal Modes ◽

Structural Variations ◽

Structural Examination ◽

Absorption Bands ◽

Synthetic Rubber ◽

Modes Of Vibration ◽

Long Chain

Abstract Infrared absorption spectra have been long recognized as a convenient means for studying the structure of organic molecules. The interpretations of the spectra are based on the energy interactions of the molecule and the radiations which arise from the vibration of the constituent atoms and molecular rotations. For simple or highly symmetrical molecules, the determination of the normal modes of vibration and the calculation of the absorbing frequencies are relatively simple and straightforward. For more complicated organic molecules, this becomes increasingly difficult because with each additional atom, the number of degrees of freedom is increased by three and the determination of the normal modes of vibration becomes practically impossible. However, interpretations can be made to a useful extent through empirical comparisons with the absorption spectra of simpler known structures. The data that have been accumulated by investigators in this field have made it possible to assign rather definite absorption frequencies to some of the chemical linkages and functional groups. These correlations which have appeared in numerous places in the literature are partially reproduced in Table I. Organic compounds generally have strong absorption bands below 1300 cm−1, to which few definite assignments can be made with certainty because the vibrations of many of the atoms of the molecule may be involved rather than a specific part of it. It is clear that such empirical relationships must be relied upon in studying the structural variations of the long chain, complex molecules which occur in butadiene and isoprene polymers and copolymers and other synthetic rubbers. This procedure has been applied to determine the effects of oxidation and of variations in monomers and polymerizing conditions on the structure of synthetic rubber. It is practically certain that physical deficiencies of synthetic rubber are due principally to the structure of the long chain molecules rather than to the chemical nature of the monomers used.

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Spectroscopic and electrical studies of all- trans β-carotene crystals

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1967.0200 ◽

1967 ◽

Vol 301 (1465) ◽

pp. 173-193 ◽

Cited By ~ 26

Keyword(s):

Electronic Absorption Spectra ◽

Dark Conductivity ◽

Electrical Measurements ◽

Absorption Bands ◽

A Value ◽

Polarization Behaviour ◽

Current Characteristics ◽

Β Carotene ◽

Weak Peak

Single crystals of all- trans β -carotene have been grown and spectroscopic, optical and electrical properties measured. Electronic absorption spectra have been measured at liquid nitrogen and room temperature, and the polarization of the absorption bands in the mono-clinic form determined. The polarization behaviour is briefly discussed. The electrical measurements include a determination of the dark conductivity, giving a value for the electrical activation energy of 1·45 eV. Some crystals were observed to give unusual voltage current characteristics and to give rise to current pulses at a steady applied voltage. Photoconductivity measurements show a weak peak at 25000 cm -1 in the region where maximum light absorption occurs, and a much stronger peak at 13300 cm -1 . The various processes which could be responsible for this and for the origin of the latter peak are discussed.

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Far infrared spectra of amorphous-Si:H thin films on polyethylene

Canadian Journal of Physics ◽

10.1139/p83-041 ◽

1983 ◽

Vol 61 (2) ◽

pp. 305-308

Author(s):

M. S. Mathur ◽

H. C. Card ◽

K. C. Kao ◽

S. R. Mejia ◽

G. C. Tabisz

Keyword(s):

Thin Films ◽

Microwave Plasma ◽

Chemical Vapour ◽

Far Infrared ◽

Substrate Material ◽

Absorption Bands ◽

Silicon Thin Films ◽

Infrared Measurements ◽

Hydrogenated Amorphous

Hydrogenated amorphous-silicon thin films (a-Si:H) were deposited by microwave plasma chemical-vapour decomposition of SiH4, on thin polyethylene sheets. The high-resolution, far infrared measurements were performed on these films in the 700–50 cm−1 region on a Nicolet far infrared interferometer. The use of polyethylene as the substrate material permitted the determination of the absorption bands at 656.4, 652, 639.4, and 543 cm−1 with a shoulder at 539 cm−1 and a broad feature at 70.8 cm−1. These features provided evidence for SiH, SiH2 (as predicted by Lucovsky et al.), and SiH3 combinations in the film, as well as far more complex systems.

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Experimental Determination of Dipole Moments of Some Benzamide Derivatives

Zeitschrift für Naturforschung A ◽

10.1515/zna-1998-0807 ◽

1998 ◽

Vol 53 (8) ◽

pp. 684-688

Author(s):

J. Heidt ◽

J. R. Heidt ◽

M. Raciniewskab

Keyword(s):

Excited State ◽

Experimental Determination ◽

Gas Phase ◽

Electronic Absorption ◽

Dipole Moments ◽

Absorption Bands ◽

Excited State Dipole Moments ◽

Benzamide Derivatives

Abstract The excited state dipole moments of some benzamide derivatives are determined. The method of solvent induced shifts of electronic absorption bands in comparison with their positions in the gas phase is used. Some regular trends revealed in the obtained data are discussed. The present results are compared with those available in the literature.

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