First-principles study of structural, electronic, elastic and thermal properties of intermetallic ternary compounds (RMn2Si2: R=Ce and Nd).

In this study, the structural, magnetic, electronic, elastic and thermal properties of the ternary intermetallic, RMn 2 Si 2 (R=Ce and Nd), compounds are presented. The study is carried out by employing the full-potential (FP) linearized augmented plane wave (LAPW) plus local orbital (lo) approach based on the density functional theory (DFT). To depict the exchange-correlation energy (an important component of total energy calculations), the local-density approximation and the local spin density approximation (LDA/LSDA) are used. Our calculated results for equilibrium lattice parameters are in good agreement with the available experimental measurements. The total energy calculations reveal the strong dependence to the distance between atomic species in these compounds. The analysis of the partial and total densities of states (DOS) of both compounds (CeMn 2 Si 2 and NdMn 2 Si 2 ) demonstrates their metallic and magnetic character as well. Whereas the calculated values of Poisson׳s ratio and B / G present their brittle makeup. At the end, using a quasi-harmonic Debye model as implemented in GIBBS code, the thermal properties were calculated. [ABSTRACT FROM AUTHOR]