Sökning: "icosahedral phase"
Visar resultat 1 - 5 av 9 avhandlingar innehållade orden icosahedral phase.
1. Disordered Icosahedral Boron-Rich Solids : A Theoretical Study of Thermodynamic Stability and Properties
Sammanfattning : This thesis is a theoretical study of configurational disorder in icosahedral boron-rich solids, in particular boron carbide, including also the development of a methodological framework for treating configurational disorder in such materials, namely superatom-special quasirandom structure (SA-SQS). In terms of its practical implementations, the SA-SQS method is demonstrated to be capable of efficiently modeling configurational disorder in icosahedral boron-rich solids, whiles the thermodynamic stability as well as the properties of the configurationally disordered icosahedral boron-rich solids, modeled from the SA-SQS method, can be directly investigated, using the density functional theory (DFT). LÄS MER
2. Phase Transformations in Computer Simulated Icosahedrally Ordered Phases
Sammanfattning : Computer simulations play a profound and fundamental role inmodern theoretical physics, chemistry and materials science. Tounderstand the complex physics of metally liquids, metals,quasicrystals and metally glasses a working model imposing thelocal and global order is needed. LÄS MER
3. Computer simulations of condensed phases with icosahedral local order
Sammanfattning : Understanding the fundamental aspects, and the formation mechanisms of glasses remains an outstanding unsolved problem of condensed-matter physics.Glass-formation in simple atomic systems is generally associated with the icosahedral local order. LÄS MER
4. Simulation of the Melting and Cooling of Palladium Clusters
Sammanfattning : The thermal behaviour of palladium clusters has been investigated using Monte Carlo simulation in various ensembles. Furthermore the energy transfer between palladium clusters and rare gas atoms has been calculated in simulated collisions aiming for a calculation of the cooling of clusters in a rare gas atmosphere. LÄS MER
5. First-principles study of configurational disorder in icosahedral boron-rich solids
Sammanfattning : This thesis is a theoretical study of configurationally disordered icosahedral boronrich solids, in particular boron carbides, using density functional theory and alloy theory. The goal is to resolve discrepancies, regarding the properties of boron carbides, between experiments and previous theoretical calculations which have been a controversial issue in the field of icosahedral boron-rich solids. LÄS MER