Crystals are solid materials with periodic and symmetric molecular patterns. The structure of a crystalline solid determines its properties, making it essential to study its structures. From the principle of minimum energy, a crystal will choose a structure with the lowest free energy F = U – TS. At low...
The ability to focus light through strongly scattering materials is opening up exciting new avenues in many fields, such as optics, computer vision, biology, and medicine, which utilize light delivery and imaging techniques. Efficient, high resolution wavefront shaping and optimization methods are crucial to enabling this new capability.
In this...
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...
The common choice in computational approximations, from 0 K to room temperature, of solid materials is to assume the structure remains unchanged at low temperatures. Often such an approximation is a very reasonable assumption. However, this approximation is not absolute and can break down even for relatively simple materials such...
Mixed anion compounds that form ZrCuSiAs-type crystal structures exhibit remarkable properties such as superconductivity at low temperatures,
hole conduction with optical transparency in the visible region, and exciton absorption at room temperature. In this thesis, properties of a selected group of materials out of the very large set of mixed...
The behavior of small atomics cluster largely depends on their geometry,
due to the high ratio of surface atoms to interior atoms. One interesting aspect
to study clusters centers around characterizing the transition behavior between
nite and bulk materials, where the ratio of surface atoms to interior atoms is
very...
This thesis presents the results from Monte Carlo calculations on classical vector spins in
face-centered-cubic (FCC) lattices. The goal of the study was to understand the effect of
interlayer coupling, dilution of magnetic atoms in the lattice, and symmetry-changing
strain.
Experimental work by T. M. Giebultowicz et al. and J....