Elastic properties of ternary arsenide SrFe2As2 and quaternary oxyarsenide LaOFeAs as basic phases for new 38-55K superconductors from first principles

TL;DR

This study uses first-principles calculations to analyze the elastic properties of SrFe2As2 and LaOFeAs, key phases in high-temperature superconductors, providing new insights into their mechanical characteristics.

Contribution

First-principles FLAPW-GGA calculations of elastic properties for SrFe2As2 and LaOFeAs, including elastic constants and moduli, with novel estimates for polycrystalline ceramics.

Findings

Elastic constants and moduli are calculated for both phases.

Numerical estimates for polycrystalline LaOFeAs and SrFe2As2 are provided.

Insights into the mechanical stability of these superconducting phases.

Abstract

Here we report the first-principle FLAPW-GGA calculations of the elastic properties of two related phases, namely, the ternary arsenide SrFe2As2 and the quaternary oxyarsenide LaOFeAs as the basic phases for the newly discovered "1111" and "122" 38-52K superconductors. The independent elastic constants (Cij), bulk moduli, compressibility, and shear moduli are evaluated and discussed. Additionally, numerical estimates of the elastic parameters of the polycrystalline LaOFeAs and SrFe2As2 ceramics are performed for the first time.