Sökning: "Fullerenes"
Visar resultat 21 - 25 av 62 avhandlingar innehållade ordet Fullerenes.
21. Ions colliding with Polycyclic Aromatic Hydrocarbons and Fullerenes
Sammanfattning : In this thesis a series of experiments on collisions between atomic projectile ions at keV energies and target vapors of either isolated molecules or van der Waals clusters is presented and analyzed. The atomic ions are produced in an Electron Cyclotron Resonance (ECR) ion source, accelerated and guided into the target volume. LÄS MER
22. Calculations of Linear and Nonlinear Optical Properties of Ionic Crystal Surfaces and Fullerenes
Sammanfattning : Electronic and optical properties of ionic crystal surfaces and fullerenes have been studied by means of cluster calculations based on the Local Density Approximation (LDA) method using a numerical LCAO approach. The calculations for the bulk, stoichiometric and non-stoichiometric (111) surfaces of the divalent ionic crystals, CaF2 and BaF2, were based on the construction of an appropriate cluster of Ba++/Ca++ and F- ions representing a local environment of the specific system. LÄS MER
23. Synthesis and characterization of nanocarbons as reinforced particles in metal composites
Sammanfattning : In this work, several scientific problems related to high pressure–high temperature (HP–HT) synthesis of new materials using fullerite as a precursor were studied: first, the mechanism of the transformation of C60 crystal into a nano-clustered graphene phase (NGP) at a pressure of 8 GPa; and second, the effect of disorder introduced into C60 crystals by ball milling prior to HP–HT synthesis on the structure and properties of the NGP. A separate set of experiments was devoted to compression of C60 precursor at unexplored before pressure of 25 GPa and elevated temperatures in search for new type of disordered carbon-based materials. LÄS MER
24. Thermal Properties of Clusters and Molecules - Experiments on Evaporation, Thermionic Emission, and Radiative Cooling
Sammanfattning : This thesis presents experiments performed on clusters and molecules, where the three channels of unimolecular decay have been studied. Evaporation from protonated and negatively charged water cluster have yielded size dependent heat capacities, where the smallest sizes with fewer than $21$ molecules show a heat capacity similar to bulk ice whereas clusters with molecules between $21$ and $300$ have a heat capacity in between that of ice and liquid water. LÄS MER
25. Synthesis and Properties of Conjugated Polymers for Photonic Devices
Sammanfattning : The synthesis and properties of new conjugated polymers for photonic devices, such as light-emitting diodes and solar cells is dealt with here. Much work was devoted to increasing the efficiencies of the devices by controlling the properties in thin films of the polymers. LÄS MER