Thermodynamic and Optical Properties of Naphthalene, Fluorene and Fluorenone Derivatives

• Main Author: Oliveira, Juliana Andreia da Silva Alves de
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01-01-2016
• Subjects: Chemistry
• ISBN: 9781083588265; 1083588265

This dissertation describes the thermodynamic and optical study of 16 fluorene derivatives, 4 fluorenone derivatives and 3 naphthalene derivatives, some of which were synthesized for this purpose.Differential scanning calorimetry analysis was performed in order to detect transitions between condensed phases and to determine their enthalpies and temperatures of transition.The crystalline vapor pressures of all the compounds studied were measured using the Knudsen mass-loss effusion method and/or a static method based on capacitance manometers. The latter method also allowed the measurement of the liquid vapor pressures of some of the compounds, enabling phase diagram representations. Sublimation and vaporization properties (standard molar enthalpy, entropy and Gibbs energy) were determined from the vapor pressure dependency with temperature, and occasionally using also Calvet microcalorimetry.The standard molar enthalpies of formation in the crystalline phase, were derived from the standard massic energy of combustion, at T = 298.15 K, measured by combustion calorimetric techniques for some of the compounds studied. For these compounds, the combination of the standard molar enthalpies of formation in the crystalline phase and the standard molar enthalpies of sublimation yielded the standard molar enthalpies of formation, in the gaseous phase. The determined results enabled the evaluation of the thermodynamic stability of the compounds by means of the Gibbs energy of formation, in crystalline and gaseous phases.After convenient tests on a new apparatus, fluorescence spectroscopic measurements were performed to determine the fluorescence quantum yield and emission properties of the compounds studied.