The Properties Of Superconductor, Reconstruction And Surface Alloy Of Semiconductor Surface

In the first part of this thesis, mechanical and electronic properties of an anti-perovskite-type superconductor ZnNNi3 as well as its isostructural and isovalent counterparts MgNNi3 and CdNNi3 have been studied using first-principles calculations. Lattice constants a, bulk modulus B, elastic constants of cubic lattice (C11, C12 and C44), compressibility K, shear modulus G, tetragonal shear modulus G', effective charges as well as electronic structures of the three materials have been calculated. Our results show that the lattice constants of the three compounds have a relationship:a(ZnNNi3)