Record Details
Field | Value |
---|---|
Title | First principles studies of optical, electronic and mechanical properties of organic molecules and solids |
Names |
Barras, Faye Lyn
(creator) Schneider, Guenter (advisor) |
Date Issued | 2014-06-12 (iso8601) |
Note | Graduation date: 2015 |
Abstract | This thesis presents the results of quantum-mechanical first principles calculations of optical, electronic and mechanical properties of organic molecules and solids, which have diverse potential applications such as photovoltaics, flexible electronics, and mechanical catalysts with applications in force sensors and self-healing materials. The electronic and optoelectronic properties of organic thin films formed from π-conjugated molecules depends strongly on the packing of the molecules in the crystal and the presence of both donor and acceptor molecules. Based on a common backbone, for example anthradithiophene, the addition of sidegroups and endgroups changes both the packing and the electronic character of the molecule. The electronic and optical properties of two families of high performance organic materials functionalized with various side- and endgroups, anthradithiophene and indenofluorene, are studied using first principles density functional calculations. I report comprehensive independent particle properties including bandstructures, HOMO and LUMO levels and effective masses, as well as the formation of type II bulk heterojunctions between donor and acceptor molecules. Mechanochemistry is a emerging field, which investigates the influence of mechanical action (forces, stress) on the direction, yield, and outcome of chemical reactions. In mechanocatalysis, mechanical force is used to break bonds in the molecule to activate a catalyst, which can for example trigger a polymerization reaction in a self-healing material. First principles total energy calculations are used to investigate a potential mechanocatalyst based on a N-heterocyclic carbene, C₁₈H₂₅N₃OS. Rupture forces as a function of force loading rates are calculated using the COGEF (COnstrained Geometries simulate External Force) model. My theoretical results are in good agreement with experimental atomic force microscopy results. |
Genre | Thesis/Dissertation |
Topic | organic |
Identifier | http://hdl.handle.net/1957/50592 |