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

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.

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Charge Transfer Complexes of N-Arylcarbamates with π-Acceptors

Zeitschrift für Naturforschung A ◽

10.1515/zna-1987-0314 ◽

1987 ◽

Vol 42 (3) ◽

pp. 284-288 ◽

Cited By ~ 1

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.

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

Molecules ◽

10.3390/molecules26072039 ◽

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.

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Chemical shifts of charge-transfer complexes and Buckingham equation

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19902131 ◽

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.

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Crystal growth and characterization of solvated organic charge-transfer complexes built on TTF and 9-dicyanomethylenefluorene derivatives

CrystEngComm ◽

10.1039/c5ce01059d ◽

2015 ◽

Vol 17 (32) ◽

pp. 6227-6235 ◽

Cited By ~ 2

Author(s):

Amparo Salmerón-Valverde ◽

Sylvain Bernès

Keyword(s):

Charge Transfer ◽

Crystal Growth ◽

Charge Transfer Complexes ◽

Organic Complexes ◽

Donor Acceptor ◽

Degree Of Charge Transfer

A series of solvated donor–acceptor organic complexes were shown to slowly release the lattice solvent while the degree of charge transfer decreases steadily. This behavior is not observed in the case of a hydrate.

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

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:20020437 ◽

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.

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PAH/PAH(CF 3 ) n Donor/Acceptor Charge‐Transfer Complexes in Solution and in Solid‐State Co‐Crystals

Chemistry - A European Journal ◽

10.1002/chem.201902712 ◽

2019 ◽

Vol 25 (59) ◽

pp. 13547-13565 ◽

Cited By ~ 1

Author(s):

Karlee P. Castro ◽

Eric V. Bukovsky ◽

Igor V. Kuvychko ◽

Nicholas J. DeWeerd ◽

Yu‐Sheng Chen ◽

...

Keyword(s):

Charge Transfer ◽

Solid State ◽

Charge Transfer Complexes ◽

Donor Acceptor

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Molecular Complexes of Cyclophanes, Part XVII Charge-Transfer Complexes of [2.2]- and [2.2.2]Paracyclophane-carbamates with π-Acceptors

Zeitschrift für Naturforschung B ◽

10.1515/znb-1987-0915 ◽

1987 ◽

Vol 42 (9) ◽

pp. 1147-1152 ◽

Cited By ~ 4

Author(s):

Aboul-fetouh E. Mourad ◽

Verena Lehne

Keyword(s):

Charge Transfer ◽

Functional Group ◽

Lone Pair ◽

Molecular Complexes ◽

Charge Transfer Complexes ◽

Electronic Interactions ◽

H Nmr ◽

Ct Complex ◽

Nitrogen Lone Pair ◽

Lone Pair Electrons

Charge-transfer (CT) complexation between some [2.2]- and [2.2.2]paracyclophane-carbamates as donors with 2,3-dichloro-5.6-dicyanobenzoquinone (DDO ) as well as tetracyanoethylene (TCNE) as π-acceptors has been evidenced by VIS. 1H NMR and IR spectroscopy. The site of interaction in the two different donor systems was determined. The results reveal no contribution of the nitrogen lone pair electrons of the carbamate functional group in the CT complexation. and the interaction is mainly of π-π* type. In addition, the existence of the transannular electronic interactions in [2.2]paracyclophane derivatives is responsible for CT complex formation.

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

Zeitschrift für Naturforschung A ◽

10.1515/zna-1974-0817 ◽

1974 ◽

Vol 29 (8) ◽

pp. 1216-1228 ◽

Cited By ~ 2

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.

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