The Redox Behavior of 9,10-Anthraquinone-2-sulfonate in Acidic Aqueous Solution

1975 ◽  
Vol 53 (24) ◽  
pp. 3757-3760 ◽  
Author(s):  
Arthur D. Broadbent ◽  
Ronald J. Melanson
Keyword(s):  
Aqueous Solution ◽  
Charge Transfer ◽  
Acidic Solution ◽  
Charge Transfer Complex ◽  
Charge Transfer Complexes ◽  
Semiquinone Radical ◽  
Redox Behavior ◽  
Acidic Aqueous Solution ◽  
Titration Curves ◽  
Potentiometric Measurements

A green intermediate, observed during reduction of 9,10-anthraquinone-2-sulfonate (A) to the corresponding anthrahydroquinone (AH2) in acidic aqueous solution, has been identified as a quinhydrone-like charge-transfer complex of A and AH2. Spectrophotometric and potentiometric measurements have shown that changes in the slope of the potentiometric titration curves with varying initial [A] are caused only by this complex [Formula: see text]and not by any semiquinone radical (AH·) or radical anion (A·−) intermediate. The very low semiquinone formation constant in acidic solution indicates that the pKa of AH· < 7.0. Electrochemically determined pKa values for similar radicals in the range 8.5–10.5 are invalid because of interference by charge-transfer complexes of this type.

Chemical shifts of charge-transfer complexes and Buckingham equation

1990 ◽  
Vol 55 (9) ◽  
pp. 2131-2137
Author(s):  
Mahboob Mohammad ◽  
Ather Yaseen Khan ◽  
Tariq Mahmood ◽  
Ismat Fatima ◽  
Riffat Shaheen ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Nmr Spectra ◽  
Charge Transfer Complex ◽  
Chemical Shifts ◽  
Charge Transfer Complexes ◽  
Aprotic Solvents ◽  
Reaction Field ◽  
H Nmr ◽  
Spherical Cavities ◽  
Dipolar Aprotic Solvents

The 1H NMR spectra of the charge-transfer complex of 1-ethyl-4-methoxycarbonylpyridinium iodide have been recorded in various dipolar aprotic solvents. An attempt is made to interpret the chemical shifts in terms of Buckingham's reaction field equation for spherical cavities. A linear dependence has been found between the δ(2,6) values and the square of dielectric function for a spherical cavity, which confirms the validity of the Buckingham equation for this class of compounds.

Gelification Effects on the Structure and Birefringence of Charge Transfer Complex Terthiophene Bisililated – TCNQ Hybrid Materials

2006 ◽  
Vol 517 ◽  
pp. 257-261
Author(s):  
N. Kancono ◽  
H.B. Senin
Keyword(s):  
Charge Transfer ◽  
Detection Limit ◽  
Hybrid Materials ◽  
Vibrational Spectra ◽  
Lamellar Structure ◽  
Radical Anion ◽  
Charge Transfer Complex ◽  
Visible Spectrum ◽  
Charge Transfer Complexes

Charge transfer complexes (CTC) can be readily introduced into materials by cohydrolysis-copolymerisation of bis-silylated ter-thiophenes as precursors with TMOS and TEOS in the presence of TCNQ. CTC formation is shown in the visible spectrum of the xerogel by the band at 850 nm characteristic of the TCNQ·- radical anion. Vibrational spectra have shown that strong vibration of C≡N bond at 2184, 2120 and 1595 cm-1 as peaks characteristics of CTC. The CTC bands are weak and the complex is easily destroyed by washing with acetone, which removes the TCNQ. The gelification effect of the charge transfer complexes on the hybrid materials of 2,5’’- bis(trime thoxysilyl)terthiophene/TCNQ/ TMOS showed that the peak with distance of more than 11.68 Å, formed by precursors and matrices, as a lamellar structure. The birefringence of xerogel BTS3T in presence of alkoxysilane showed that the value is near the detection limit of 0.1 – 0.4 x 10-3, which is weaker than BTS3T / THF with the birefringence value of 4.5 x 10-3.

Photooxidation of m-Phenoxytoluene at Colloidal Titanium Dioxide/Non-Aqueous Solution Interfaces

1989 ◽  
Vol 42 (8) ◽  
pp. 1351 ◽  
Author(s):  
E Blatt ◽  
DN Furlong ◽  
AWH Mau ◽  
WHF Sasse ◽  
D Wells
Keyword(s):  
Aqueous Solution ◽  
Titanium Dioxide ◽  
Charge Transfer ◽  
Intermediate Product ◽  
Charge Transfer Complexes ◽  
Analysis Technique ◽  
Aqueous Solvent

The selective photooxidation of m- phenoxytoluene to m-phenoxybenzaldehyde has been investigated in the system m-phenoxytoluene/O2/titanium dioxide/non-aqueous solvent/light. In acetonitrile the conversion was found to be c. 20% with starting concentrations of m-phenoxytoluene in the range 0.05-0.5 mol dm-3. Adsorption of m-phenoxytoluene, m-phenoxybenzaldehyde or the intermediate product m-phenoxybenzyl alcohol from acetonitrile on titanium dioxide was not detectable by an equilibration/centrifugation/supernatant analysis technique. Photoemission and photoexcitation measurements, however, showed that m- phenoxytoluene and m-phenoxybenzyl alcohol, but not m-phenoxybenzaldehyde , formed charge-transfer complexes with titanium dioxide surfaces. The selectivity of the photooxidation is explained in terms of pathways involving these charge-transfer complexes.

scholarly journals Fermi level pinned molecular donor/acceptor junctions: reduction of induced carrier density by interfacial charge transfer complexes

2020 ◽  
Vol 8 (43) ◽  
pp. 15199-15207
Author(s):  
Paul Beyer ◽  
Eduard Meister ◽  
Timo Florian ◽  
Alexander Generalov ◽  
Wolfgang Brütting ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Fermi Level ◽  
Carrier Density ◽  
Charge Transfer Complex ◽  
Charge Transfer Complexes ◽  
Interfacial Charge Transfer ◽  
Fermi Level Pinning ◽  
Donor Acceptor ◽  
Interfacial Charge

Charge transfer complex (CPX) formation at a donor–acceptor interface reduces the amount of Fermi-level pinning induced interfacial charge transfer.

Photochemical transformation of an iron(iii)–arsenite complex in acidic aqueous solution

2016 ◽  
Vol 15 (3) ◽  
pp. 431-439 ◽  
Author(s):  
Ivan P. Pozdnyakov ◽  
Wei Ding ◽  
Jing Xu ◽  
Long Chen ◽  
Feng Wu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Charge Transfer ◽  
Flash Photolysis ◽  
Laser Flash Photolysis ◽  
Laser Flash ◽  
Photochemical Transformation ◽  
Acidic Aqueous Solution ◽  
Metal Charge ◽  
Metal Charge Transfer

An Fe(iii)–As(iii) complex was characterized by UV/Vis spectra and its laser flash photolysis via ligand-to-metal charge transfer resulted in the intermediate of Fe(ii)–As(iv).

scholarly journals Water-Soluble Visible Light Sensitive Photoinitiating System Based on Charge Transfer Complexes for the 3D Printing of Hydrogels

Polymers ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 3195
Author(s):  
Hong Chen ◽  
Mehdi Vahdati ◽  
Pu Xiao ◽  
Frédéric Dumur ◽  
Jacques Lalevée
Keyword(s):  
Charge Transfer ◽  
3D Printing ◽  
Visible Light ◽  
Water Solubility ◽  
Charge Transfer Complex ◽  
Water Soluble ◽  
Charge Transfer Complexes ◽  
Free Radical Photopolymerization ◽  
Potential Applications ◽  
A Charge

The development of visible-light 3D printing technology by using water-soluble initiating systems has attracted widespread attention due to their potential applications in the manufacture of hydrogels. Besides, at present, the preparation of water-soluble photoinitiators suitable for visible light irradiation (such as LEDs) still remains a challenge. Therefore, this work is devoted to developing water-soluble photoinitiators (PI)/photoinitiating systems (PIS) upon irradiation with a LED @ 405 nm. In detail, a new water-slightly-soluble chalcone derivative dye [(E)-3-(4-(dimethylamino) phenyl)-1-(4-(2-(2-(2-methoxyethoxy) ethoxy) ethoxy) phenyl) prop-2-en-1-one] was synthesized here and used as a PI with a water-soluble coinitiator, i.e., triethanolamine (TEA) which was also used as an electron donor. When combined together, a charge transfer complex (CTC) formed immediately which exhibited excellent initiating ability for the free radical photopolymerization of poly(ethyleneglycol)diacrylate (PEG-DA). In light of the powerful CTC effect, the [dye-TEA] CTC could not only exhibit enhanced water solubility and mechanical properties but could also be effectively applied for 3D printing. This CTC system is environmentally friendly and cost-saving which demonstrates a great potential to prepare hydrogels via photopolymerization.

Charge transfer complex-doped single-walled carbon nanotubes with reduced correlations between electrical conductivity and Seebeck coefficient for flexible thermoelectric generators

2020 ◽  
Vol 8 (14) ◽  
pp. 4827-4835 ◽  
Author(s):  
Jingjuan Tan ◽  
Hongfeng Huang ◽  
Dagang Wang ◽  
Shihui Qin ◽  
Xu Xiao ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Electrical Conductivity ◽  
Charge Transfer ◽  
Seebeck Coefficient ◽  
Charge Transfer Complex ◽  
Single Walled Carbon Nanotubes ◽  
Charge Transfer Complexes ◽  
Thermoelectric Generators ◽  
Flexible Thermoelectric ◽  
Walled Carbon Nanotubes

Charge transfer complexes as far more superior dopants for carbon-based flexible thermoelectric generators.

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