THE ULTRAVIOLET ABSORPTION SPECTRA OF THE FERRIC ION AND ITS FIRST HYDROLYSIS PRODUCT IN AQUEOUS SOLUTIONS

1957 ◽  
Vol 35 (9) ◽  
pp. 1002-1009 ◽  
Author(s):  
R. C. Turner ◽  
Kathleen E. Miles
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Absorption Spectra ◽  
Perchloric Acid ◽  
Hydrolysis Product ◽  
Ultraviolet Absorption ◽  
Ferric Ion ◽  
Absorption Bands

The absorption spectra of the ferric ion and its first hydrolysis product in an aqueous solution of perchloric acid was determined. The Fe3+ ion has two absorption bands, one with a maximum at 240 mμ and another which extends into the region below 200 mμ. The FeOH2+ ion also has two absorption bands, the maxima of which occur at 300 mμ and 205 mμ. A figure shows the magnitude of the absorption of each of these ions from 200 to 350 mμ.

Halogen-Substitution Effect on the Optical Absorption Bands of Uracil*

1974 ◽  
Vol 29 (9-10) ◽  
pp. 493-495 ◽  
Author(s):  
Wolfgang Lohmann
Keyword(s):  
Optical Absorption ◽  
Linear Function ◽  
Absorption Spectra ◽  
Electron Affinity ◽  
Substitution Effect ◽  
Ultraviolet Absorption ◽  
Red Shift ◽  
Electron Affinities ◽  
Absorption Bands ◽  
Extinction Coefficients

Abstract The ultraviolet absorption spectra of uracil and its 5-halogenated derivatives have been in ­ vestigated in regard to the electron attracting properties of the substituents. It could be shown that the position of the two absorption bands is proportional to the inverse of the electronegativity; the extinction coefficients are a linear function of the electron affinities. In this way, the red shift obtained upon substitution with halogens can be explained. Also, the decrease in absorbance of the absorption bands at λ > 250 nm, occuring concomitant­ ly, is understandable. The increase in absorbance with increasing electron affinity, as observed in the case of the absorption bands at λ < 250 nm, might question the assumption that this band is due to a higher pi -pi* excitation

Kinetics of the Decomposition of Sulphur Dicyanide in Aqueous Solution

1962 ◽  
Vol 15 (2) ◽  
pp. 211 ◽  
Author(s):  
W Kitching ◽  
RH Smith ◽  
IR Wilson
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Nucleophilic Substitution ◽  
Perchloric Acid ◽  
Reaction Path ◽  
Acid Solutions ◽  
Kinetics Of

The kinetics and stoicheiometry of the decomposition of aqueous solutions of sulphur dicyanide have been studied at temperatures between 0-70 �C and in media ranging from dilute perchloric acid to pH 7. The predominant reaction is nucleophilic substitution at carbon, but in perchloric acid solutions an alternative reaction path has been revealed.

THE ULTRAVIOLET ABSORPTION SPECTRA OF ALIPHATIC NITRAMINES, NITROSAMINES, AND NITRATES

1949 ◽  
Vol 27b (11) ◽  
pp. 828-860 ◽  
Author(s):  
R. Norman Jones ◽  
G. Denis Thorn
Keyword(s):  
Absorption Spectrum ◽  
Absorption Spectra ◽  
Ultraviolet Spectrum ◽  
Ultraviolet Absorption ◽  
Absorption Bands ◽  
Structure Formula ◽  
New Compounds

The ultraviolet absorption bands associated with the following groups have been investigated in a variety of compounds of known structure:[Formula: see text]The groups may be characterized by the ultraviolet spectrum, and the number of each type of group present in a given compound may be estimated from an analysis of the shape and intensity of the absorption spectrum. These correlations have been applied to the elucidation of the structure of new compounds isolated in the course of the investigation of the chemistry of 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX).

A Pulse Radiolysis Study of the Reaction of the Sulfate Radical Ion in Aqueous Solutions of Styrene

1979 ◽  
Vol 32 (12) ◽  
pp. 2611 ◽  
Author(s):  
NA McAskill ◽  
DF Sangster
Keyword(s):  
Aqueous Solutions ◽  
Absorption Spectra ◽  
Pulse Radiolysis ◽  
Cation Radical ◽  
Ultraviolet Absorption ◽  
Sulfate Radical ◽  
Transient Species ◽  
Acetonitrile Solutions ◽  
Type Radical

The ultraviolet absorption spectra of the transient species formed during the pulse radiolysis of styrene and peroxydisulfate (S2O82)solutions showed that a benzyl-type radical was formed from styrene and the SO4- radical. The effect of adding Cl- was also studied. These results are in conflict with the claim1 that a phenylethyl radical was formed from SO4-' via the styrene cation radical. That study was made on acetonitrile solutions of styrene, S2O82-, CuCl2 and LiCl and the present results suggest that up to 70% of the SO4-' radicals may have been converted into Cl2-1 radical which then reacted with styrene.

scholarly journals Protonation constants of hydroxybenzenes in hydrochloric acid

1999 ◽  
Vol 64 (9) ◽  
pp. 533-538
Author(s):  
D.S. Veselinovic ◽  
M.V. Obradovic ◽  
S.B. Tosic
Keyword(s):  
Hydrochloric Acid ◽  
Aqueous Solutions ◽  
Absorption Spectra ◽  
Protonation Constants ◽  
Acidity Function ◽  
Absorption Bands ◽  
Graphic Dependence ◽  
Mineral Acids ◽  
Hammett Acidity Function

The absorption spectra of monohydroxybenzene (Fen), 1,3-dihydroxybenzene (Rez), 1,4-dihydroxybenzene (Hi), 1,2,3-trihydroxybenzene (Pg) and 1,3,5-trihydroxy-benzene (Fg) in aqueous solutions of hydrochloric acid with different values of the Hammett acidity function(H0) have two absorption bands in the region between 190-220 nm and 260-290 nm. This behavior is similar in another mineral acids (H2SO4, H3PO4, HClO4). The absorbance decreases with increasing of acidity (with decreasing of H0 values) because of O-protonation. The absorption maxima shift to longer wave-lengths, and the graphic dependence of the absorption of the second band as a function of H0 gives characteristic S-curves. These curves show the different effect of the acid on the form the protonation of the investigated hydroxybenzenes. The potonation constants of the hydroxybenzenes were calculated: pKFen=-1.95; pKRez=-2.40; pKHi= -1.93; pKPg=-2.95; pKFg=-1.83.

scholarly journals Исследование изменений в спектре поглощения современных хлоринсодержащих препаратов для фотодинамической терапии и метиленового синего в результате воздействия светодиодного излучения с длиной волны 656± 10 nm

2020 ◽  
Vol 129 (7) ◽  
pp. 972
Author(s):  
А.В. Беликов ◽  
Ю.В. Семяшкина ◽  
С.Н. Смирнов ◽  
А.Д. Тавалинская
Keyword(s):  
Methylene Blue ◽  
Aqueous Solutions ◽  
Absorption Spectra ◽  
Exposure Time ◽  
Spectral Range ◽  
Color Model ◽  
Absorption Bands ◽  
Lab Color Model ◽  
Cie Lab ◽  
The Impact

The changes in absorption spectra of aqueous solutions of modern chlorine-containing photosensitizing preparations "Revixan" (Areal, Russia) and "Chloderm" (Chloderm, Russia) depending on the intensity of LED radiation with wavelength of 656 ± 10 nm and exposure time were studied in spectral range 600-700 nm. The parameters of the CIE Lab color model of the image of "Revixan" aqueous solution before and after LED exposure were investigated. The changes in absorption spectra of aqueous solutions of methylene blue with different initial concentrations arising after exposure to LED radiation with intensity of 180 ± 20 mW/cm2 were studied in the spectral range 400-900 nm. It was shown that the impact of LED radiation changes the absorption spectra of the studied preparations and increases the parameter L (lightness) of the CIE Lab color model for "Revixan". An increase in the LED radiation intensity and exposure time leads to a decrease in absorption for "Revixan" and "Chloderm" in spectral range 600-700 nm and to a shift of the peaks of absorption bands lying in this range towards a longer wavelength. The impact of LED radiation on aqueous solutions of methylene blue leads to a decrease in their absorption in spectral range 400-900 nm.

Electronic absorption spectra for copper(II) polyamine complexes

1970 ◽  
Vol 23 (5) ◽  
pp. 981 ◽  
Author(s):  
GR Hedwig ◽  
JL Love ◽  
HKJ Powell
Keyword(s):  
Aqueous Solution ◽  
Field Strength ◽  
Absorption Spectra ◽  
Chain Length ◽  
Electronic Absorption ◽  
Thermodynamic Stability ◽  
Electronic Absorption Spectra ◽  
Ultraviolet Absorption ◽  
Ligand Field ◽  
Nitrogen Donor

The preparations and visible and ultraviolet absorption spectra are reported for a series of copper(11) complexes with linear and cyclic aliphatic ligands which each have four nitrogen donor atoms. Data are compared with that for 16 analogous complexes. For linear polyamines of different chain length the ligand field strength, as denoted by vmax (visible), is found to increase with increasing thermodynamic stability of the copper(11) complex in aqueous solution. For linear and cyclic ligands the ligand field strength is a maximum for complexes containing a combination of five- and six-membered chelate rings.

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