scholarly journals Binding Modes of a Phenylpyridinium Styryl Fluorescent Dye with Cucurbiturils

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 5111
Author(s):  
Adrien Paudics ◽  
Dóra Hessz ◽  
Márton Bojtár ◽  
Benjámin Gyarmati ◽  
András Szilágyi ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Polyethylene Glycol ◽  
Quantum Yield ◽  
Fluorescence Quantum Yield ◽  
Phenyl Ring ◽  
Intramolecular Charge Transfer ◽  
Theoretical Calculations ◽  
Binding Modes ◽  
Pyridinium Ring ◽  
Solvatochromic Dye

In order to explore how cucurbituril hosts accommodate an N-phenyl-pyridinium derivative guest, the complexation of the solvatochromic dye, 4-(4-(dimethylamino)styryl)-1-phenylpyridinium iodide (PhSt) with α,α′,δ,δ′-tetramethyl-cucurbit[6]uril (Me4CB6) and cucurbit[7]uril (CB7) was investigated by absorption spectroscopic, fluorescence and NMR experiments. In aqueous solutions, PhSt forms 1:1 complexes with both cucurbiturils, the complex with CB7 has a higher stability constant (Ka = 6.0 × 106 M−1) than the complex with Me4CB6 (Ka = 1.1 × 106 M−1). As revealed by NMR experiments and confirmed by theoretical calculations, CB7 encapsulates the whole phenylpyridinium entity of the PhSt cation guest, whereas the cavity of Me4CB6 includes only the phenyl ring, the pyridinium ring is bound to the carbonyl rim of the host. The binding of PhSt to cucurbiturils is accompanied by a strong enhancement of the fluorescence quantum yield due to the blocking of the deactivation through a twisted intramolecular charge transfer (TICT) state. The TICT mechanism in PhSt was characterized by fluorescence experiments in polyethylene glycol (PEG) solvents of different viscosities. The PhSt-CB7 system was tested as a fluorescence indicator displacement (FID) assay, and it recognized trimethyl-lysine selectively over other lysine derivatives.

Effects of molecular geometry on the efficiency of intramolecular charge transfer–based luminescence in o-carboranyl-substituted 1H-phenanthro[9,10-d]imidazoles

2022 ◽  
Author(s):  
Sehee Im ◽  
Chan Hee Ryu ◽  
Mingi Kim ◽  
Dong Kyun You ◽  
Sanghee Yi ◽  
...  
Keyword(s):  
Optical Properties ◽  
Charge Transfer ◽  
Phenyl Ring ◽  
Intramolecular Charge Transfer ◽  
Molecular Geometry

Herein, we compared the optical properties of four compounds with an o-carborane cage linked to 1H-phenanthro[9,10-d]imidazole at the ortho- (oPC), meta- (mPC), or para-position (pPC) of the 2-phenyl ring or...

SPECTRAL PROPERTIES OF A BENZOTHIAZOLE DYE MODIFIED WITH POLYETHYLENE GLYCOL

2021 ◽  
Vol 88 (6) ◽  
pp. 852-857
Author(s):  
A. A. Maskevich
Keyword(s):  
Absorption Spectrum ◽  
Polyethylene Glycol ◽  
Quantum Yield ◽  
Fluorescence Quantum Yield ◽  
Plasma Proteins ◽  
Spectral Properties ◽  
Amyloid Fibrils ◽  
Strong Dependence ◽  
Molecular Rotor ◽  
Blood Plasma Proteins

The spectral properties of a new benzothiazole dye modified with polyethylene glycol have been investigated. A strong dependence of the fluorescence quantum yield on the viscosity and polarity of the medium has been shown, i.e. the conjugation of the dye with polyethylene glycol does not lead to the loss of the properties of the molecular rotor, while significantly reduces its aggregation. When incorporated into amyloid fibrils, the quantum yield of the dye increases by more than 40 times; the new dye can be regarded as an efficient fluorescent probe for amyloid fibrils detection and research. In this case, not only the intensity, but also the position of the absorption spectrum can be used as a sensitive parameter. The presence of blood plasma proteins (albumins) in the solution has practically no effect on the position of the absorption spectrum and has little effect on the fluorescence intensity of the probe.

Intramolecular charge transfer-based linear and nonlinear optical properties of a D–π–A–π–D type organic chromophore: Experimental and computational approach

2021 ◽  
Author(s):  
Mohd Mehkoom ◽  
Abid Ali ◽  
Mohammad Jane Alam ◽  
Farman Ali ◽  
S. M. Afzal ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Nonlinear Optical ◽  
Continuous Wave ◽  
Intramolecular Charge Transfer ◽  
Theoretical Calculations ◽  
Nonlinear Refraction ◽  
Photon Absorption ◽  
Nonlinear Optical Susceptibility ◽  
Linear And Nonlinear ◽  
Organic Chromophore

In the sight of the present demand of scientific exploration in nonlinear optics (NLO), we synthesized a symmetric donor–[Formula: see text]–acceptor–[Formula: see text]–donor (D–[Formula: see text]–A–[Formula: see text]–D) type organic chromophore [2-[2,6-di((E)-styryl)]-4H-pyran-4-ylidene]malononitrile (M1) for linear and nonlinear optical studies. The structural character of the compound M1 was confirmed using 1H NMR, [Formula: see text]C NMR, and IR spectroscopy. The intramolecular charge transfer (ICT) in molecule M1 has been analyzed using absorption and fluorescence spectrometry in different nonpolar and polar solvents. The optical bandgap, optical conductivity, and linear refractive index of M1 were also calculated using UV–Vis absorption spectrum in CHCl3. The thermogravimetric analysis (TGA) was also carried out to check the thermal stability of the compound M1 and it was found to be thermally stable up to 200∘C. Furthermore, the third-order optical nonlinearity in M1 has been investigated elaborately using the [Formula: see text]-scan technique with a continuous wave (CW) diode laser at 520[Formula: see text]nm. The nonlinear absorption ([Formula: see text]), nonlinear refraction ([Formula: see text]), and nonlinear optical susceptibility ([Formula: see text]) were computed for various solution concentrations as well as several laser powers and the magnitude of all the parameters were found to vary linearly with concentration and power. The magnitude of two-photon absorption cross-section ([Formula: see text]) was also calculated and found to be of the order of 10[Formula: see text] GM. The optical limiting performance of the compound was also studied in different solution concentrations using the same laser. Furthermore, DFT and TD-DFT theoretical calculations were performed for the support of experimental results.

scholarly journals Fluorescence quantum yield rationalized by the magnitude of the charge transfer in π-conjugated terpyridine derivatives

2016 ◽  
Vol 18 (42) ◽  
pp. 29387-29394 ◽  
Author(s):  
Marie Humbert-Droz ◽  
Claude Piguet ◽  
Tomasz A. Wesolowski
Keyword(s):  
Dipole Moment ◽  
Charge Transfer ◽  
Quantum Yield ◽  
Excited States ◽  
Charge Separation ◽  
Fluorescence Quantum Yield ◽  
Molecular Design ◽  
Electron Hole ◽  
Two Measures

Two measures of charge separation in ground and excited states (length of the change in dipole moment and the electron–hole distance) provide a remarkable tool for the molecular design of a fluorescent polyaromatic antenna.

Two-photon absorption of styryl-quinolinium, -pyridinium, and -barbituric acid derivatives, and intramolecular charge transfer

2001 ◽  
Vol 79 (2) ◽  
pp. 174-182 ◽  
Author(s):  
XiaoMei Wang ◽  
Chun Wang ◽  
WenTao Yu ◽  
YuFang Zhou ◽  
Xian Zhao ◽  
...  
Keyword(s):  
Dipole Moment ◽  
Charge Transfer ◽  
Barbituric Acid ◽  
Intramolecular Charge Transfer ◽  
Theoretical Calculations ◽  
Photon Absorption ◽  
Amino Groups ◽  
Element Analysis ◽  
Two Photon Absorption ◽  
Two Photon

A series of new chromophores, styryl-parent end-capped with various donors, and with barbituric acid, methyl-pyridinium, and methyl-quinolinium as the acceptors, have been synthesized and characterized by element analysis or X-ray diffraction. Using the Z-scan system, their two-photon absorption (TPA) cross-section values (δ) have been determined under excitation with 10 Hz, and 1064 nm, 35 ps mode-locked Nd:YAG laser pulse in DMF with do= 0.05 M. The effective δ value is as high as 10.9 × 10–48 cm4 s per photon for trans-4-(4'-N,N-diphenyl amino) styryl-N-methyl quinolinium iodide (DPASQI). The δ value increases from barbituric acid- to pyridinium- to quinolinium-derivatives apparently due to the increase in both the conjugated degree and planarity; however, when the acceptor is fixed, the δ value increases from dialkyl amino groups to diphenyl amino groups even though the latter is a weaker donor than the dialkyl amino groups. Theoretical calculations confirm that the increased distortion from planarity for the barbituric acid derivative makes its δ value decrease. The relatively large δ value for quinolinium- or pyridinium-derivatives originates from larger intramolecular charge transfer, which can be characterized by the difference of dipole moment (Δµge) between the S0 and S1, and the transition dipole moment (Mee') between S1 and S2.Key words: two-photon absorption, intramolecular charge transfer, styryl-quinolinium, styryl-pyridinium, styryl-barbituric acid.

Phenanthroimidazole derivatives showing mild intramolecular charge transfer, high quantum yield and their applications in OLEDs

2021 ◽  
Author(s):  
Swati Dixit ◽  
Chandan Gupta ◽  
Tanveer Habib Tadavi ◽  
KRS Chandrakumar ◽  
Sangita Bose ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Quantum Yield ◽  
Organic Electronics ◽  
Intramolecular Charge Transfer ◽  
Biological Applications ◽  
High Quantum Yield ◽  
High Quantum ◽  
Material Sciences

Phenanthroimidzole (Phen-I) has attracted the attention of researchers for applications in material sciences including organic electronics and biological applications. Herein, we designed small Phen-I derivatives showing mild bipolar character and...

Solvatochromism and mechanochromism observed in a triphenylamine derivative

2019 ◽  
Vol 75 (5) ◽  
pp. 839-844
Author(s):  
Chunyang Guo ◽  
Qi Zhang ◽  
Bingqing Zhu ◽  
Bin Zhu ◽  
Weiqun Zhou ◽  
...  
Keyword(s):  
Optical Properties ◽  
Charge Transfer ◽  
Solid State ◽  
Intramolecular Charge Transfer ◽  
Theoretical Calculations ◽  
Fluorescent Dye ◽  
Fluorescent Properties ◽  
Polar Solvents ◽  
Solid States ◽  
Triphenylamine Derivative

A donor–π–acceptor fluorescent dye, 4-[N,N-di(4-phenyl)amino]benzaldehyde 4-chlorobenzoyl hydrazone (TPA-CBH), based on a triphenylamine derivative (TPA) and 4-chlorobenzoyl hydrazine (CBH) was designed and synthesized. The optical properties of this luminogen were investigated in solutions as well as in the solid states. In the intramolecular charge-transfer (CT) mechanism, TPA-CBH exhibits solvatochromism when dissolved in various polar solvents. Aggregation-induced emission was observed with the changes of tetrahydrofuran/water ratios. In the solid state, mechanochromic fluorescence is observed when the samples are stressed under different conditions. Based on structural analyses and theoretical calculations, it is found that intra- and intermolecular CT processes play a key role in the diversity of fluorescent properties.

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