2006/02/07 by P. Jiji Thomas Joseph, P Jiji Thomas Joseph, Prabhakar P. Singh +1
Materials Science · Physics and Astronomy · #Bulk modulus #Coherent potential approximation #Condensed matter physics #Debye model #Density functional theory #Density of states #Diffraction #Electron #Electronic structure #Fermi level #Lattice (music) #Lattice constant #Materials science #Phonon #Physics #Quantum mechanics #Rare-earth and actinide compounds #Superconductivity in MgB2 and Alloys #Thermal Expansion and Ionic Conductivity #Thermodynamics #cond-mat.mtrl-sci #cond-mat.supr-con
paper · pdf · doi:10.1088/0953-8984/18/23/007
published as J. Phys.:Condens. Matter 18 (2006) 5333-5347 · 19 pages, 15 figures
arxiv created 2006/02/07 · openalex publication_date 2006/05/26 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
First-principles, density-functional-based electronic structure calculations are employed to study the changes in the electronic properties of ZnC y Ni 3 and MgC y Ni 3 using the Korringa–Kohn–Rostoker coherent-potential approximation method in the atomic sphere approximation (KKR-ASA CPA). As a function of decreasing C atomic percentage, we find a steady decrease in the lattice constant and bulk modulus in both alloys. However, the pressure derivative of the bulk modulus displays an opposite trend. Following the Debye model, which relates the pressure derivative of the bulk modulus to the average phonon frequency of the crystal, it can thus be argued that ZnCNi 3 and its disordered alloys possess a different phonon spectrum in comparison to its MgCNi 3 counterparts. This is further justified by the marked similarity we find in the electronic structure properties such as the variation in the density of states and the Hopfield parameters calculated for these alloys. The effects on the equation of state parameters and the density of states at the Fermi energy, for partial replacement of Mg by Zn, are also discussed.