Organic charge-transfer complexes for the selective accommodation of aromatic isomers using anthracene derivatives and TCNQ

2016 ◽  
Vol 40 (6) ◽  
pp. 5277-5284 ◽  
Author(s):  
Arshad Khan ◽  
Mingliang Wang ◽  
Rabia Usman ◽  
Jiao Lu ◽  
Hao Sun ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Charge Transfer Complexes ◽  
Anthracene Derivatives ◽  
Ct Complexes

Four organic-charge transfer (CT) complexes (Ct1–Ct4) have been reported. Ct1 discerns p-xylene in the presence of a xylene mixture.

scholarly journals Charge Transfer Complexes of Ketotifen with 2,3-Dichloro-5,6-dicyano-p-benzoquinone and 7,7,8,8-Tetracyanoquodimethane: Spectroscopic Characterization Studies

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 2039
Author(s):  
Gamal A. E. Mostafa ◽  
Ahmed Bakheit ◽  
Najla AlMasoud ◽  
Haitham AlRabiah
Keyword(s):  
Charge Transfer ◽  
Spectroscopic Characterization ◽  
Molar Ratio ◽  
Charge Transfer Complexes ◽  
Physical Parameters ◽  
Spectrophotometric Methods ◽  
Theoretical Approaches ◽  
The Stability ◽  
Ct Complexes

The reactions of ketotifen fumarate (KT) with 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) as π acceptors to form charge transfer (CT) complexes were evaluated in this study. Experimental and theoretical approaches, including density function theory (DFT), were used to obtain the comprehensive, reliable, and accurate structure elucidation of the developed CT complexes. The CT complexes (KT-DDQ and KT-TCNQ) were monitored at 485 and 843 nm, respectively, and the calibration curve ranged from 10 to 100 ppm for KT-DDQ and 2.5 to 40 ppm for KT-TCNQ. The spectrophotometric methods were validated for the determination of KT, and the stability of the CT complexes was assessed by studying the corresponding spectroscopic physical parameters. The molar ratio of KT:DDQ and KT:TCNQ was estimated at 1:1 using Job’s method, which was compatible with the results obtained using the Benesi–Hildebrand equation. Using these complexes, the quantitative determination of KT in its dosage form was successful.

One-dimensionality and neutral-to-ionic transition of some mixed-stack charge-transfer complexes

2002 ◽  
Vol 12 (9) ◽  
pp. 357-360
Author(s):  
M. Buron ◽  
E. Collet ◽  
M. H. Lemée-Cailleau ◽  
H. Cailleau ◽  
T. Luty ◽  
...  
Keyword(s):  
Phase Transition ◽  
Charge Transfer ◽  
Charge Transfer Complexes ◽  
X Ray Diffraction ◽  
One Dimensional ◽  
Giant Dielectric ◽  
Ionic Transition ◽  
The One ◽  
Ct Complexes ◽  
Dimerization Process

Mixed-stack charge-transfer (CT) complexes undergoing the neutral-ionic (N-I) phase transition are molecular materials formed of stacks where electron donor (D) and acceptor (A) molecules regularly alternate. In the N phase, the CT is low and molecules are situated on inversion centers, while in the I phase, the increase of CT is accompanied by a lattice distortion (dimerization process and symmetry breaking). The one-dimensional (1D) architecture triggers the chain multistability by stabilizing lattice-relaxed (LR)-CT excitations ...D° A° D° A° $(D^+A^-)(D^+A^-)(D^+A^-)$ Do A" D° A° D°... These 1D nano-scale objects are at the heart of the equilibrium N-I phase transition and govern the fascinating physical properties such as giant dielectric response or photo-induced phase transformations. In this contribution, the 1D character of these critical excitations will be demonstrated by direct observation using high resolution X-Ray diffraction.

Charge Transfer Complexes of N-Arylcarbamates with π-Acceptors

1987 ◽  
Vol 42 (3) ◽  
pp. 284-288 ◽  
Author(s):  
Aboul-fetouh E. Mourad
Keyword(s):  
Charge Transfer ◽  
Electron Density ◽  
Nmr Spectra ◽  
Charge Transfer Complexes ◽  
H Nmr ◽  
Ct Complexes

The charge-transfer (CT) complexes of some N-arylcarbamates as donors with a number of π-acceptors have been studied spectrophotometrically. The Lewis basicities of the N-arylcarbamates as well as the types of interactions are discussed. The 1H-NMR spectra of some CT complexes with both 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) and 7,7,8,8 tetracyanoquinodimethane (TCNQ) indicate a decrease of the electron density on the donor part of the complex.

Charge Transfer Complexes of Aromatic Nitrocompounds with Disubstituted Naphthalenes. I.Spectroscopic Investigation of the Donor Behaviour of the 2,6- and 23-Dimethylnaphthalene

1984 ◽  
Vol 39 (12) ◽  
pp. 1274-1278 ◽  
Author(s):  
M. H. Abdel-Kader ◽  
R. M. Issa ◽  
M. M. Ayad ◽  
M. S. Abdel-Mottaleb
Keyword(s):  
Charge Transfer ◽  
Spectral Characteristics ◽  
Charge Transfer Complexes ◽  
Element Analysis ◽  
H Nmr ◽  
Aromatic Nitrocompounds ◽  
Donor Acceptor ◽  
The Difference ◽  
Donor Behaviour ◽  
Ct Complexes

The charge transfer complexes of 2,3- (I) and 2,6-Dimethylnaphthalenes (II) as electron donors with tri- and di-nitrobenzenes as electron acceptors are prepared and investigated by element analysis, IR. 1H nmr and electronic absorption spectroscopy. The results showed that I yields CT complexes of 1:1 type only while II is capable of forming 1 : 1 and 1 : 2 (donor: acceptor) compounds. The spectral characteristics of the CT complexes are pointed out and discussed. The difference in the donor behaviour between I and II is explained in the light of PPP-MO calculations.

scholarly journals Mobile and Trapped Triplet States in Single Crystals of Charge Transfer Complexes

1974 ◽  
Vol 29 (8) ◽  
pp. 1216-1228 ◽  
Author(s):  
H. Möhwald ◽  
E. Sackmann
Keyword(s):  
Charge Transfer ◽  
Delayed Fluorescence ◽  
Charge Transfer Complexes ◽  
Zero Field ◽  
Triplet States ◽  
Zero Field Splitting ◽  
Triplet Energy ◽  
Molecular Arrangement ◽  
Ct Complexes ◽  
Triplet Excitons

Homogeneously doped crystals of charge transfer (CT-) complexes were grown by incorporating aromatic guest donors in host CT-crystals. The host crystals contained 1,2.4,5-tetracyanobenzene (TCNB) as acceptor and deuterated aromatic electron donors. By using such doped crystals CT complexes in a well defined configuration may be studied. The triplet states of the guest complexes were used as ESR spectroscopic probes in order to determine the molecular arrangement in the host lattice. The zero-field-splitting (ZFS) parameters, D and E, of the triplet energy traps were determined and the degree of electron derealization in the triplet state was calculated from these values. In some cases a very strong guest host interaction (multicomplex formation) was established. A method for the determination of CT-triplet energies is described (accuracy 200 cm-1) . The phosphorescence spectrum of the anthracene-TCNB complex was obtained from the delayed emission spectra of different anthracene doped CT-crystals. The vibronic structure is identical to that of anthracene, while the O-O-band of the complex is blue shifted by 600 cm-1. It is shown that the undoped anthracene-TCNB crystal exhibits P-type delayed fluorescence and that the triplet exciton diffusion in this crystal is nearly temperature independent. In the undoped biphenyl-TCNB crystal E-type delayed fluorescence originating from the thermal depopulation of the mobile triplet excitons is established. The remarkable differences of the two types of triplet excitons are interpreted in terms of the different polarity in the triplet states of the two CT-crystals.

scholarly journals Über die Bildung von Molekülkomplexen bei der Feldionisation organischer Moleküle

1971 ◽  
Vol 26 (12) ◽  
pp. 2063-2066
Author(s):  
H. D. Beckey ◽  
M. D. Migahed
Keyword(s):  
Charge Transfer ◽  
Hydrogen Bonds ◽  
Sandwich Structure ◽  
Mass Spectra ◽  
Field Ionization ◽  
Charge Transfer Complexes ◽  
Ionization Mass ◽  
Organic Substances ◽  
Ct Complexes

Hetero-dimer ions are observed in the field ionization mass spectra of aniline-nitrobenzene mixtures, and also in mixtures of some other organic substances which yield charge-transfer complexes in solutions. It is shown that the structure of the hetero-dimer ions is different from the sandwich structure of the corresponding CT-complexes in solutions. Arguments are given for assuming hydrogen bonds between the components of the complexes, with an additional weak CT-bond

Photochemical reactions of charge-transfer complexes. The irradiation of the charge-transfer complexes between 1,4-, 1,5-, and 2,3-dimethoxynaphthalenes and 1,2-dicyanoethylenes

1980 ◽  
Vol 58 (9) ◽  
pp. 918-927 ◽  
Author(s):  
P. C. Wong ◽  
D. R. Arnold
Keyword(s):  
Charge Transfer ◽  
Triplet State ◽  
Ion Pair ◽  
Photochemical Reactions ◽  
Association Constants ◽  
Charge Transfer Complexes ◽  
Polar Solvents ◽  
Photostationary State ◽  
Ct Complex ◽  
Ct Complexes

The first part of this paper describes the experimental search for a donor which would complex preferentially one of the isomers of 1,2-dicyanoethylene. This involved measuring the association constants (KcDA) of the charge-transfer (ct) complexes of several dimethoxynaphthalenes (DMN) with maleonitrile (MN) and fumaronitrile (FN). From the measured KcDA, we found that MN complexes more strongly than FN with 1,4- and 1,5-DMN but that FN complexes more strongly with 2,3-DMN than does MN. These results are explained in terms of more than one favourable geometry for the ct complexes, since the donors are relatively large compared to the acceptors.Irradiation of the ct complexes between 1,4-, 1,5-, or 2,3-DMN and 1,2-dicyanoethylene led to isomerization of the olefins. The photostationary state depends on the absorption spectra of the ct complexes formed between the donor and the isomeric olefins. From spectroscopic and photo-CIDNP studies, we find evidence that the isomerization in polar solvents takes place via the triplet state of the olefin. The triplet is formed from the radical ion pair resulting after excitation of the ct complex.

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