Probing into the global structural prediction, physical and electronic properties of A-X (A = Ca, Sr, Ba; X = La, Nd, Sm) binary intermetallic alloys

We predict the crystal structures of A-X (A = Ca, Sr, Ba; X = La, Nd, Sm) binary alloys at ambient conditions using the particle swarm optimization algorithm jointly with density functional theory. The stability of the predicted structures has checked from the density functional calculations. The structural stability is examined from phonon dispersion and density of states too. Then we studied the electronic properties of these compounds for the predicted low energy structures. The bonding nature is derived through the electronic structures of the predicted phases. Using the stress-strain approach we compute the elastic constants. Using this, elastic moduli’s, B/G and Poisson’s ratio are derived. Moreover, the brittleness, plasticity and anisotropy in different directions of these alloys are discussed in detail. Obtained sound wave velocities are displayed. Debye temperature, heat capacity, thermal expansion coefficient and Gruneisen parameters are computed and discussed. •The structure prediction of A-X (A = Ca, Sr, Ba; X = La, Nd, Sm) intermetallics has been investigated by calypso combined with ab-initio calculation.•The calculated elastic constants and phonon dispersion curve confirmed the mechanical and dynamical stability of these alloys.•The Ca3Nd in Fm-3m compound is stiffness due to the higher Shear modulus and Young’s modulus compared to other compounds.•The Ba3X (X = La, Nd, Sm) and Ca3Nd compounds have the fragile in their respective structure and other compounds exhibit ductile behavior.•All the compounds exhibit that the metallic behavior.