A DFT Study on Electronic Structures and Elastic Properties of AgX (X=C, N) in Rock Salt Structure

The electronic structure of AgX (X = C and N) is calculated within the framework of density functional theory (DFT) using full potential linearized augmented plane wave (FP-LAPW) method with the generalized gradient approximation (GGA). The ground state properties for the compounds in rock salt structure are determined. The structural and electronic parameters such as lattice constant, bulk modulus, energy band diagram and density of states are calculated. The energy band diagram and density of states show that both AgC and AgN in rock salt structure possess metallic character and has Fermi energy 0.63 Ry and 0.53 Ry respectively. The energy separation between the lowest band and valence band (E_g^Ns-Np), and the band wide (E_p - E_s) of valence band of AgN is higher as compared to AgC. The elastic constants C₁₁, C₁₂, C₄₄ obtained using volume conserving technique are found to be satisfied for stability conditions: (C₁₁-C₁₂)>0, (C₁₁+2C₁₂)>0, C₁₁>0, C₄₄>0 and hence AgC, AgN crystallizes in rock salt structure is a stable compound.