An energy optimised Tree Branch Methodology was developed to overcome the multiple minima problem in molecular mechanics calculations of acyclic molecules. Target molecules were assembled one heavy atom at a time from small precursors, and the energy minimized after each addition. The number of structures to be minimised was significantly reduced by following the lowest energy path in the Tree Branch Method. Comparison of the calculated configurations to minimum energy structures obtained from complete conformational search is made. / The compression of fatty acid monolayers in Langmuir-Blodgett trough experiments at the air/water interface was modelled using a two dimensional array. The minimum energy configuration of the acids was obtained using the Tree Branch Methodology, and the water coordination number determined by comparison of calculated and experimentally measured dipole moments. The variation in measured dipole moments as the hydrated head group was compressed were explained. / Minimum energy configurations of known surfactant molecules used in the preparation of water-in-oil emulsion explosives were obtained through the Tree Branch Methodology, and the optimised geometries used to calculate structural parameters assuming standard van der Waals radii around each atom. Comparison of the structural parameters to the stability of the emulsions in which the surfactants were used, allowed preliminary structural criteria to be established. Based on the structural criteria, a number of new families of surfactant head group were designed, and preliminary rules for matching head to tail group combinations proposed.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.39313 |
| Date | January 1992 |
| Creators | Villamagna, Fortunato |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Chemistry.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001291090, proquestno: NN74781, Theses scanned by UMI/ProQuest. |
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