Spectroscopic properties and redox chemistry of the phosphorescent excited state of octahydrotetrakis(phosphorus pentoxide)diplatinate(4-) ion (Pt2(P2O5)4H84-)

1981 ◽  
Vol 103 (26) ◽  
pp. 7796-7797 ◽  
Author(s):  
Chi Ming Che ◽  
Leslie G. Butler ◽  
Harry B. Gray
2001 ◽  
Vol 05 (07) ◽  
pp. 600-607 ◽  
Author(s):  
ISABELLE M. DIXON ◽  
JEAN-PAUL COLLIN

Four diads consisting of a free-base or zinc aryl-porphyrin associated with two ruthenium(II) bis(terdentate) complexes (non-cyclometallated Ru ( N 6) or cylometallated Ru ( N 5 C )) have been synthesized. The strong electron-withdrawing properties of the Ru ( N 6) as compared to the Ru ( N 5 C ) complex have been illustrated by their electrochemical and spectroscopic properties. Emission spectra of the diads and the reference compounds have shown that very efficient fluorescence quenching occurs, probably by energy transfer processes from the porphyrin to the 3MLCT excited state of the ruthenium unit.


2008 ◽  
Vol 6 (3) ◽  
pp. 443-449 ◽  
Author(s):  
D. Svechkarev ◽  
G. Karpushina ◽  
L. Lukatskaya ◽  
A. Doroshenko

AbstractThree 2-(benzimidazol-2-yl)-3-hydroxychromone derivatives were synthesized. Their spectroscopic and fluorescent properties, due to excited state intramolecular proton transfer (ESIPT) from OH to carbonyl, were studied. Theoretical possibility of an alternative intramolecular H-bonding and experimental evidence for such behavior are discussed.


2016 ◽  
Vol 45 (25) ◽  
pp. 10297-10307 ◽  
Author(s):  
Oliver J. Stacey ◽  
Benjamin D. Ward ◽  
Simon J. Coles ◽  
Peter N. Horton ◽  
Simon J. A. Pope

Ligands based upon 4-carboxamide-2-phenylquinoline have been functionalised with naphthyl, anthracenyl and pyrenyl chromophores. The pyrene appended Pt(ii) complex shows excited state equilibration and a long emission lifetime.


1987 ◽  
Vol 42 (4) ◽  
pp. 395-405 ◽  
Author(s):  
N. Detzer ◽  
W. Baumann ◽  
B. Schwager ◽  
J.-C. Fröhling ◽  
C. Brittinger

The synthesis of several compounds related to ADMA are described in detail. These compounds are characterized by their mass, NMR, and IR-spectra. In addition, the solvent dependent shift of the fluorescence as well as the effect of an electric field on the fluorescence have been measured. The results are in agreement with a two-state model assuming the simultaneous fluorescence from a weakly polar and a highly polar state with dipole moment μ. μ2/a3 (a is Onsager’s radius) has been determined from both effects. The results are in good agreement with an excited state dipole moment of about 60 • 10-30Cm, in the polar state.


2001 ◽  
Vol 79 (4) ◽  
pp. 358-363 ◽  
Author(s):  
Andrey S Klymchenko ◽  
Turan Ozturk ◽  
Vasyl G Pivovarenko ◽  
Alexander P Demchenko

With the focus of designing new fluorescent probes, four new 3-hydroxy-chromone derivatives bearing benzofuran and naphthofuran groups were synthesized. They show bathochromic absorption shifts relative to 3-hydroxyflavone with the ability of retention to display the excited-state proton transfer. Disruption of the planarity by the methyl group in the furan ring leads to a decrease of both the extinction coefficient and the contribution of long wavelength absorption band, while molecules without a methyl group showed two distinct absorption bands. Shifts to longer wavelengths are also observed in fluorescent spectra, and the absence of the methyl group results in a dramatic increase of fluorescence quantum yield and lifetime. Of the extended 3-hydroxychromone derivatives, 3-hydroxy-2-naphtho[2,1-b]furan-2-yl-chromone has shown comparable, and in some cases better, absorption and fluorescence properties than the 3-hydroxychromones synthesized so far, which make it a highly promising candidate as molecular probe for analytical chemistry, biophysics, and cellular biology.Key words: benzo- and naphthofuryl-3-hydroxyflavone, synthesis, electronic spectra, fluorescence, excited state proton transfer.


Molecules ◽  
2021 ◽  
Vol 26 (23) ◽  
pp. 7247
Author(s):  
Sandra Gómez ◽  
Esra N. Soysal ◽  
Graham A. Worth

In this work, we report a complete analysis by theoretical and spectroscopic methods of the short-time behaviour of 4-(dimethylamino)benzonitrile (DMABN) in the gas phase as well as in cyclohexane, tetrahydrofuran, acetonitrile, and water solution, after excitation to the La state. The spectroscopic properties of DMABN were investigated experimentally using UV absorption and fluorescence emission spectroscopy. The computational study was developed at different electronic structure levels and using the Polarisable Continuum Model (PCM) and explicit solvent molecules to reproduce the solvent environment. Additionally, excited state quantum dynamics simulations in the diabatic picture using the direct dynamics variational multiconfigurational Gaussian (DD-vMCG) method were performed, the largest quantum dynamics “on-the-fly” simulations performed with this method until now. The comparison with fully converged multilayer multiconfigurational time-dependent Hartree (ML-MCTDH) dynamics on parametrised linear vibronic coupling (LVC) potentials show very similar population decays and evolution of the nuclear wavepacket. The ring C=C stretching and three methyl tilting modes are identified as the responsible motions for the internal conversion from the La to the Lb states. No major differences are observed in the ultrafast initial decay in different solvents, but we show that this effect depends strongly on the level of electronic structure used.


Author(s):  
Adil Nameh Ayaash

The present work concerns by study of spectroscopic properties for Beryllium monobromide BeBr. Franck Condon Factor of BeBr molecule had been calculated theoretically for ground state X2Σ+ and excited state A2Π by special integrals by depending on spectroscopic constants for this molecule. The Dissociation energy and potential curves of this molecule is studied in this work by using Hua potential function, the results of potential curves and Franck Condon Factors converge with other researchers results.


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