Balpeteği yapısında SiC üzerindeki hataların ve ilave atomların etkisinin ilk prensiplerden incelenmesi

In this thesis a study of electronic and magnetic properties of two dimensional(2D), single layer of silicon carbide (SiC) in hexagonal structure and its quasi 1Darmchair nanoribbons are presented by using first-principles plane wave method.In order to reveal dimensionality effects, a brief study of 3D bulk and 1D atomicchain of SiC are also included. The stability analysis based on the calculationof phonon mode frequencies are carried out for different dimensionalities. It isfound that 2D single layer SiC in honeycomb structure and its bare and hydrogenpassivated nanoribbons are ionic, non magnetic, wide band gap semiconductors.The band gap further increases upon self-energy corrections. Upon passivation ofSi and C atoms at the edges of nanoribbon with hydrogen atoms, the edge statesare discarded and the band gap increases. The effect of various vacancy defects,adatoms and substitutional impurities on electronic and magnetic properties in2D single layer SiC and in its armchair nanoribbons are also investigated. Some ofthese vacancy defects and impurities, which are found to influence physical propertiesand attain magnetic moments, can be used to functionalize SiC honeycombstructures for novel applications.