Molecular rotational motions are known to influence both Raman scattering of light and nuclear spin relaxation. Therefore, the application of Raman bandshape analysis and NMR relaxation time measurements to probe molecular dynamics in liquids will provide us with a deeper understanding of the dynamical behavior and structure of molecules in the liquid phase. Presented here are (i) studies of molecular reorientation of acetonitrile in the neat liquid phase and in solution by Raman bandshape analysis and NMR relaxation; (ii) studies of reorientational dynamics and internal rotation in transition metal clusters by NMR relaxation.

The behavior of surfactants in solution has been and still is of scientific, technological, and industrial interest. The micelle forming compounds sodium N( octyloxycarbonyl)sarcosinate (NaOcSarc), and sodium N-(decyloxycarbonyl)sarcosinate (NaDecSarc) show in aqueous solution two lH NMR N-methyl peaks arising from a possible cis- or trans-conformation. The relative population of the N-methyl peaks depends mostly on the concentration of surfactant indicating micelle formation. Upon heating the two peaks start to coalesce and finally appear as one single peak . The temperature range in which this phenomenon occurs is from 25°C to 65°C. The primary interest of this study was to determine the activation parameters of rotation about the carbonyl-nitrogen (C-N) bond. Dynamic nuclear magnetic resonance spectroscopy was employed to approach this problem. A complete bandshape analysis was performed in order to calculate the free energy (G++), enthalpy (H++), and entropy (S++) of activation. The effect of a different counter ion (Li+) and sodium chloride salt addition were tested for possible changes of the activation parameters. Studies in nonaqeous solvents were conducted with the free acid form of the mentioned carbarnates. Dimethylsulfoxide and chloroform were chosen as organic solvents for these particular experiments. The critical micellar concentrations of all surfactants were determined, and the assignment of the individual N-methyl peaks to the correspondend conformation could be unambiguously shown by a two dimensional NMR experiment. The cmc's show strong salt dependence. The effect of a lithium as an alternative counter ion has a less drastic effect. Micellization seems not to occur in the free acid cases. Interestingly, the surfactants show stronger salt dependence than micellization dependence upon the activation parameters, indicating that solvent exposure occurs at the C-N partial double bond and considerable deformation of the ideal spherical shape.

Geoffrey Knight, Jr. [and] B.T. Feld. / "June 10, 1949." Based on a thesis. / Bibliography: p. 23. / Army Signal Corps Contract No. W36-039-sc-32037. Project No. 102B. Dept. of the Army Project No. 3-99-10-022.

Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references. / xi, 133 leaves, bound ill. 29 cm

Thesis (Ph.D.)--McMaster University, 2004. / Supervisor: Michael J. McGlinchey. Includes bibliographical references (leaves 243-267).

Thesis (Ph. D.)--University of Wisconsin, 1967. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliography.

Thesis (Ph. D.)--University of Delaware, 2005. / Principal faculty advisor: Yong Duan, Dept. of Chemistry & Biochemistry. Includes bibliographical references.

No description available.

The independent interconversion of alpha-N-carbobenzoxy-D-glucosaminide to the beta- form, and vice versa, suggests that the proper treatment of the rate data must involve a system of opposing reactions. It is evident from the data cited in the preceding chapter that such opposing rates must necessarily involve the HCl which is included in the reaction mixture. Thus, as the first approach to the analyzed data, it is reasonable to suppose that the rate law for opposing second-order rates will apply. However, it is also apparent from the data that the concentration of HCl used in all this work exceeds the glycoside concentration by a factor of about one hundred times. Therefore, the postulated system of opposing second order processes may be reduced to a system of opposing [pseudo-first-order processes. Such a system can be formulate as follows: [see PDF]

Graduation date: 1992