The Experts below are selected from a list of 381 Experts worldwide ranked by ideXlab platform

Hungerford Graham - One of the best experts on this subject based on the ideXlab platform.

  • Preferential formation of mixed dimers in aluminium containing porphyrin–phthalocyanine systems: A photophysical study
    2005
    Co-Authors: Pereira, Mário R., Ferreira João, Hungerford Graham
    Abstract:

    Article in PressThe interaction of chloroaluminium phthalocyanine and aluminium porphyrin in solution was studied using UV–visible and fluorescence techniques. The spectra of the porphyrin alone exhibited new bands attributed to aggregates and a value of -12.6 kJ mol-1 for the Enthalpy of Dimerization was obtained. A small Dimerization constant of 5.8 x 103 M-1 was found for phthalocyanine homodimers and preferential formation of mixed dimers over porphyrin homodimers was observed experimentally and supported by molecular modelling. kd and ΔH values of 5.7 x 104 M-1 and -21.1 kJ mol-1 were found in the mixed system, along with an enhancement in phthalocyanine fluorescence.info:eu-repo/semantics/publishedVersio

Pereira, Mário R. - One of the best experts on this subject based on the ideXlab platform.

  • Preferential formation of mixed dimers in aluminium containing porphyrin–phthalocyanine systems: A photophysical study
    2005
    Co-Authors: Pereira, Mário R., Ferreira João, Hungerford Graham
    Abstract:

    Article in PressThe interaction of chloroaluminium phthalocyanine and aluminium porphyrin in solution was studied using UV–visible and fluorescence techniques. The spectra of the porphyrin alone exhibited new bands attributed to aggregates and a value of -12.6 kJ mol-1 for the Enthalpy of Dimerization was obtained. A small Dimerization constant of 5.8 x 103 M-1 was found for phthalocyanine homodimers and preferential formation of mixed dimers over porphyrin homodimers was observed experimentally and supported by molecular modelling. kd and ΔH values of 5.7 x 104 M-1 and -21.1 kJ mol-1 were found in the mixed system, along with an enhancement in phthalocyanine fluorescence.info:eu-repo/semantics/publishedVersio

Ferreira João - One of the best experts on this subject based on the ideXlab platform.

  • Preferential formation of mixed dimers in aluminium containing porphyrin–phthalocyanine systems: A photophysical study
    2005
    Co-Authors: Pereira, Mário R., Ferreira João, Hungerford Graham
    Abstract:

    Article in PressThe interaction of chloroaluminium phthalocyanine and aluminium porphyrin in solution was studied using UV–visible and fluorescence techniques. The spectra of the porphyrin alone exhibited new bands attributed to aggregates and a value of -12.6 kJ mol-1 for the Enthalpy of Dimerization was obtained. A small Dimerization constant of 5.8 x 103 M-1 was found for phthalocyanine homodimers and preferential formation of mixed dimers over porphyrin homodimers was observed experimentally and supported by molecular modelling. kd and ΔH values of 5.7 x 104 M-1 and -21.1 kJ mol-1 were found in the mixed system, along with an enhancement in phthalocyanine fluorescence.info:eu-repo/semantics/publishedVersio

Sadel Deena - One of the best experts on this subject based on the ideXlab platform.

  • Effects of Ionic Strength on Aqueous Solutions of Xanthene Dyes
    2010
    Co-Authors: Huynh Nina, Sadel Deena
    Abstract:

    Xanthene dyes tend to aggregate even in dilute aqueous solutions causing dimer formation, or higher order aggregates, which are strongly affected by structure, concentration, ionic strength, temperature, and the presence of other organic molecules. Rhodamine 6G was studied as a function of temperature in the range of 10 - 75°C in the absence and presence of ~2.0 M aqueous sodium chloride. The presence of electrolytes clearly induces dimer formation. The DATAN (DATa ANalysis) 3.1 software was used to determine the relative amounts of monomer and dimer present in solution, and the equilibrium constant for Dimerization, in the presence of electrolytes, is 8.4 x 103. The Gibbs free energy of dimer formation is -22.4 kJ/mol and a van’t Hoff plot gives a standard Enthalpy of Dimerization of -39.2 kJ/mol. Then the standard entropy of dimer formation is calculated to be -56.5 J/(mol*K).ar

Huynh Nina - One of the best experts on this subject based on the ideXlab platform.

  • Effects of Ionic Strength on Aqueous Solutions of Xanthene Dyes
    2010
    Co-Authors: Huynh Nina, Sadel Deena
    Abstract:

    Xanthene dyes tend to aggregate even in dilute aqueous solutions causing dimer formation, or higher order aggregates, which are strongly affected by structure, concentration, ionic strength, temperature, and the presence of other organic molecules. Rhodamine 6G was studied as a function of temperature in the range of 10 - 75°C in the absence and presence of ~2.0 M aqueous sodium chloride. The presence of electrolytes clearly induces dimer formation. The DATAN (DATa ANalysis) 3.1 software was used to determine the relative amounts of monomer and dimer present in solution, and the equilibrium constant for Dimerization, in the presence of electrolytes, is 8.4 x 103. The Gibbs free energy of dimer formation is -22.4 kJ/mol and a van’t Hoff plot gives a standard Enthalpy of Dimerization of -39.2 kJ/mol. Then the standard entropy of dimer formation is calculated to be -56.5 J/(mol*K).ar