Holzwarth, Moritz2022-11-082022-11-0820221821209079http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-ds-125106http://elib.uni-stuttgart.de/handle/11682/12510http://dx.doi.org/10.18419/opus-12491The thermodynamical stability of a simple 2D model quasicrystal is analysed using the theory of the phason elastic free energy. Atoms in the crystal interact via a double-well potential called the Lennard-Jones Gauß-potenital. The essential mechanisms that support the quasicrystal's free energy are atom jumps called phasonic flips. The distribution of such flips in a crystal is computed in dependency of the crystal lattice, which is parameterized by a 2x2-matrix called the phasonic strain. This computation is fully analytic and is based on the popular cut-and-project-scheme for quasicrystals. The quasicrystal is found to be instable at low temperature but stabilized at high temperature due to large entropy. This is in accordance with an MD-simulation from 2008 that used the LJG-Interaction-potential for the first time.eninfo:eu-repo/semantics/openAccess530masterThesis