Thesis (Ph. D.)--Lehigh University, 1999. / Includes bibliographical references and vita.

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[Typescript] / 237 p. : ill. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.1967) University of Adelaide, Dept. of Physical and Inorganic Chemistry

Thesis (Ph.D. 1967) University of Adelaide, Dept. Physical and Inorganic Chemistry. / Typescript.

Thesis (Ph. D.)--University of Illinois, 1917. / Biography. "Reprinted from the Journal of the American Chemical Society, vol. XXXIX, no. 8, page 1545."

Thesis (M.S.)--University of Wisconsin--Madison, 1964. / eContent provider-neutral record in process. Description based on print version record. Bibliography: l. 65-67.

Excess thermodynamic properties have been determined for several binary liquid mixtures with the aim of testing various thermodynamic theories and postulates. Excess molar enthalpies, HEm, have been determined using an LKB flow microcalorimeter and excess molar volumes, VEm, have been determined using an Anton Paar vibrating tube densitometer. The activity coefficients at infinite dilution ƴ∞₁₃, have been determined using an atmospheric pressure gas-liquid chromatograph. The excess molar enthalpies and the excess molar volumes have been measured at 298.15 K for systems involving the bicyclic compounds decahydronaphthalene (decalin), 1,2,3,4-tetrahydronaphthalene (tetralin), bicyclohexyl, or cyclohexylbenzene mixed with 1- hexene, 1-hexyne, 1-heptene, 1-heptyne, cyclohexene, 1,3-cyclohexadiene, 1,4- cyclohexadiene, or benzene. These excess properties have also been measured for systems where the bicyclic compound has been replaced with benzene, cyclohexane or n-hexane. The results show defmite trends related to the size, shape, and the degree of unsaturation of the component molecules. The Flory theory has been used to predict excess molar enthalpies and excess molar volumes for {(a bicyclic compound or benzene or cyclohexane or n-hexane) +(an n-alkane or a 1-alkene or a 1-alkyne or a cycloalkane or cyclohexene or a cycloalkadiene or benzene)}. The one parameter equations offer reasonably good correlations between the predicted and the experimental results. More insight into the origins of the contnbutions to the excess thermodynamic properties for these systems has been gained by considering the approximate equations of Patterson and co-workers, which separate the interactional and the free volume contributions to the excess molar enthalpy and the excess molar volume. The one parameter equations have adequately rationalized a good deal of the observed behaviour for HEm and VEm. The theory of Liebermann and co-workers, which does not employ any adjustable parameters, has not been as successful at predicting the excess thermodynamic properties for the above systems. The activity coefficients at infinite dilution have been measured at 278.15 K, 288.15 K and 298.15 K for n-bexane, 1-bexene, 1-hexyne, n-heptane, 1-heptene, 1-heptyne, cyclohexane, cyclohexene, 1,3-cyclohexadiene, 1,4-cyclohexadiene, and benzene, in decalin, tetralin, bicyclohexyl, and cyclohexylbenzene. Solvent losses from the column have been accounted for by an extrapolation procedure. The activity coefficient results together with the HEm and VEm values have been used to calculate the partial molar excess thermodynamic properties of mixing at infinite dilution. The partial molar excess properties at infinite dilution for decalin mixtures are similar to those for bicyclohexyl mixtures. There is also a similarity between the properties of the tetralin mixtures and the cyclohexylbenzene mixtures. The cycloalkadienes, benzene and the 1-alkynes exhibit a strong dissociation effect on being mixed with the saturated solvents, decalin and bicyclohexyl, but associate strongly with tetralin and with cyclohexylbenzene. The Flory theory bas been used to predict activity coefficients at infinite dilution from the experimentally determined HEm results for { (n-bexane or 1-hexene or 1-hexyne or naheptane or 1-heptene or 1-beptyne) + (a bicyclic compound)}. The theory is much better at predicting values for mixtures where both components are either saturated molecules or are unsaturated molecules than for {saturated + unsaturated} mixtures.

The theory of charge-transfer spectra has been described briefly with respect to the energy, symmetry and intensity of charge-transfer transitions. The concepts derived were then applied to the special case of double charge-transfer absorption in donor/acceptor complexes between substituted benzenes and tetracyanoethylene. A first-order perturbation method treating specifically the perturbation of the substituted donor cation was discussed in detail since it is of particular importance to the interpretation of multiple charge-transfer spectra as investigated here. A detailed experimental study of the various aspects of double charge-transfer absorption has been presented in the second chapter. The equilibrium constants and extinction coefficients for both charge-transfer transitions of a number of increasingly methoxy-substituted benzene/TCNE complexes have been reported. TCNE was found to form stable complexes with these donors. For some complexes the variation of the relative molar extinction coefficients with temperature of the two c.-t. transitions of a complex was measured. A small but definite difference in heat of formation was obtained for transitions I and II. This was taken as evidence for the existence of two configurational isomers in the complexes measured. Extensive data on the effect of polar and nonpolar solvents on the positions, relative intensities, band widths and band separations of the two transitions, respectively, for the p-dimethoxy/TCNE and o-dimethoxy/TCNE complexes were reported. In nonpolar solvents the effect of solvent on the charge-transfer energy could be described as a function of the refractive index of the solvent. In polar solvents, red as well as blue shifts of the charge-transfer bands relative to their position in cyclohexane were observed. The TCNE/ substituted benzene complexes showed high solvent specificity in many polar solvents. The data obtained are summarized in terms of potential energy curves of the complex in dependence on refractive index and polarity of solvent. Such representation could account for most of the effects observed. The dependence of charge-transfer energy on ionization potential for the TCNE/substituted benzene complexes was found to be decidedly anomalous when compared to the behavior of other π-acceptors. The problem was investigated in detail. It could be shown that the abnormal behavior of the TCNE complexes is related to the structure of the acceptor. In the last section the observed double charge-transfer spectra of substituted benzene/TCNE complexes have been compared with theory. However, the perturbation parameters as derived from experiment were found to vary, contrary to theory which defines them as constants. The discrepancy could be resolved when the coulomb interactions of the charge-transfer processes were taken into account. / Science, Faculty of / Chemistry, Department of / Graduate

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by Chan Kwok Kwan. / Chinese title: / Thesis (M.Phil.) -- Chinese University of Hong Kong, 1983