The fluorescence spectra in cyclohexane of a series of benzanilides(BAs) with different \%para\% substituents at the anilino moiety revealed that BAs emitted dual fluorescence, with one normal weak emission at ca . 33...The fluorescence spectra in cyclohexane of a series of benzanilides(BAs) with different \%para\% substituents at the anilino moiety revealed that BAs emitted dual fluorescence, with one normal weak emission at ca . 330 nm and an abnormally long wavelength emission ranging from 460 to 550 nm. The long wavelength emission was found strongly dependent of the electron donating capacity of the substituent at the anilino moiety and a stronger electron donating substituent led to a red shift in the emission. The energies of the long wavelength emission of the BAs were correlated to the oxidation potentials of the donors, E \-\{D/D +\}, and a nice linear correlation was found with a slope of +0 66, which clearly pointed to the charge transfer character of the emissive state for the long wavelength emission and the high decoupling extent of the charges in the CT state. This is the first report that shows the direct evidence for the CT nature. The results might be of significance in understanding the photophysics of peptide and protein and in designing novel fluorescent chemosensors.展开更多
Five new mixed ligand complexes Cu(X PTLA)phe[PTLA=2 (COO)C6H4CONHC6H4,X=H,2 Cl,2 CH3,2 OCH3,4 OCH2CH3,Phe=β phenylalanine] were synthesized and characterized by means of elemental analysis, infrared and ultraviolet ...Five new mixed ligand complexes Cu(X PTLA)phe[PTLA=2 (COO)C6H4CONHC6H4,X=H,2 Cl,2 CH3,2 OCH3,4 OCH2CH3,Phe=β phenylalanine] were synthesized and characterized by means of elemental analysis, infrared and ultraviolet as well as thermogravimetical analysis. It is indicated that in mixed ligand complexes coordination occurs through carboxylate oxygen, oxygen of amino in 2 [(substituted phenylamino) carbonyl] benzoic acid and carboxyl oxygen, nitrogen of amino in amino acid.Stereo configuration of the complex is plane square. Three ways,MacCllum and Tammer ,Coats and Redfern and Zsako methods, were adopted to calculate the values of the apparent decomposition activation energies, the activation entropies, the reaction orders and the frequency factors, respectively. The results show that the reaction orders are all 2/3. Studies of the mechanism of these reactions state that these reactions all fit the kinetic equation 1-(1-α)1/3=kt.The changes of activation energies and activation entropies were discussed.展开更多
文摘The fluorescence spectra in cyclohexane of a series of benzanilides(BAs) with different \%para\% substituents at the anilino moiety revealed that BAs emitted dual fluorescence, with one normal weak emission at ca . 330 nm and an abnormally long wavelength emission ranging from 460 to 550 nm. The long wavelength emission was found strongly dependent of the electron donating capacity of the substituent at the anilino moiety and a stronger electron donating substituent led to a red shift in the emission. The energies of the long wavelength emission of the BAs were correlated to the oxidation potentials of the donors, E \-\{D/D +\}, and a nice linear correlation was found with a slope of +0 66, which clearly pointed to the charge transfer character of the emissive state for the long wavelength emission and the high decoupling extent of the charges in the CT state. This is the first report that shows the direct evidence for the CT nature. The results might be of significance in understanding the photophysics of peptide and protein and in designing novel fluorescent chemosensors.
文摘Five new mixed ligand complexes Cu(X PTLA)phe[PTLA=2 (COO)C6H4CONHC6H4,X=H,2 Cl,2 CH3,2 OCH3,4 OCH2CH3,Phe=β phenylalanine] were synthesized and characterized by means of elemental analysis, infrared and ultraviolet as well as thermogravimetical analysis. It is indicated that in mixed ligand complexes coordination occurs through carboxylate oxygen, oxygen of amino in 2 [(substituted phenylamino) carbonyl] benzoic acid and carboxyl oxygen, nitrogen of amino in amino acid.Stereo configuration of the complex is plane square. Three ways,MacCllum and Tammer ,Coats and Redfern and Zsako methods, were adopted to calculate the values of the apparent decomposition activation energies, the activation entropies, the reaction orders and the frequency factors, respectively. The results show that the reaction orders are all 2/3. Studies of the mechanism of these reactions state that these reactions all fit the kinetic equation 1-(1-α)1/3=kt.The changes of activation energies and activation entropies were discussed.
