Global ETD Search

11	THE EFFECT OF MOLECULAR DESIGN ON SPIN DENSITY LOCALIZATION AND RADICAL-INITIATED DEGRADATION OF CONJUGATED RADICAL CATIONS Kaelon Athena Jenkins (16613448) 19 July 2023 (has links) <p> Radical species are essential in modern chemistry. In addition to fundamental chemistry, their unique chemical bonding and distinct physicochemical features serve critical functions in materials science in the form of organic electronics. Due to their high reactivity, radicals of the main group element are often transient. In recent years, remarkably stable radicals are often stabilized by π-delocalization, sterically demanding side groups, carbenes, and weakly coordinating anions. The impacts of modifications such as electron-donating, electron-withdrawing, and end-capping on the spin density distribution and thermodynamic and kinetic stability of archetypal radical-driven processes such as dimerization are not well understood. This dissertation aims to track the perturbation of spin density from EDG and EWG modifications, provide mechanistic insight into the radical-initiated reactions of conjugated radical cations, and establish correlations between molecular design and thermochemical properties and their resulting kinetic stability by computationally evaluating these characteristics against experimental data. The disclosed connections give useful new recommendations for the rational design of thermodynamically and kinetically stable novel materials.</p> Physical properties of materials Structure and dynamics of materials Electrochemistry Computational chemistry Molecular and organic electronics conjugated radicals redox spin density concentration Structure Properties Relationship degradation analytics dimerization dynamics thermodynamic stability study Kinetic Stabilities Correlated Physical Chemistry of Materials electrochromic compounds radical stability quantum mechanical approaches Transition state ab initio calculations mass spectra prediction electronic properties
12	CRYSTAL PLASTICITY OF PENTAERYTHRITOL TETRANITRATE (PETN) Jennifer Oai Lai (17677422) 24 April 2024 (has links) <p dir="ltr">We investigate the crystal plasticity and shock response of single crystal and polycrystalline pentaerythritol tetranitrate (PETN) using mesoscale finite element simulations. The model includes the Mie-Grüneisen Equation of State and a single crystal plasticity model. Simulations with single crystals with different orientations are tested using our plasticity model under shock compression to explore shear stress and slip. Parameters regarding the Mie-Grüneisen Equation of State are also verified in various orientations from 0.50 to 1.75 km/s. A polycrystalline PETN sample with varying grain sizes and orientations are subjected to shock loading with impact velocities ranging from 0.25 to 0.75 km/s. We study how differences in shock orientation affect slip and stress in PETN at different shock strengths.</p> Structure and dynamics of materials Aerospace materials Aerospace structures Solid mechanics energetic materials PETN crystal plasticity modeling crystal orientation shock single crystal polycrystal material finite elements simulations Continuum & Computational Mechanics slip systems equation of state (EoS)
13	SURFACE CHEMISTRY CONTROL OF 2D NANOMATERIAL MORPHOLOGIES, OPTOELECRONIC RESPONSES, AND PHYSICOCHEMICAL PROPERTIES Jacob Thomas Lee (12431955) 12 July 2022 (has links) <p>This dissertation describes how the surface chemistries of 2D nanomaterials can be modified to alter overall material properties. Specifically, through a focus of the ligand-surface atom bonding in addition to the overall ligand structure we highlight the ability to direct morphological outcomes in lead free halide perovskites, maximize optoelectronic responses in substoichiometric tungsten oxide, and alter physicochemical properties titanium carbide MXenes. </p> Transition metal chemistry Macromolecular materials Nanochemistry Optical properties of materials Physical properties of materials Structure and dynamics of materials Supramolecular chemistry Colloid and surface chemistry Localized Surface Plasmon Resonance MXenes WO3-x 2D nanomaterials perovskite lead-free perovskite surface chemistry covalent attachment 2D morphology optoelectronic characteristics Inorganic Chemistry Optical Properties of Materials Physical Chemistry of Materials Synthesis of Materials Transition Metal Chemistry Chemical Characterisation of Materials Colloid and Surface Chemistry

Page generated in 0.1184 seconds