Lattice Dynamics, Mechanical Properties, Electronic Structure and Magnetic Properties of Equiatomic Quaternary Heusler Alloys CrTiCoZ (Z =Al,Si) using first principles calculations

Eesha Andharia; Hind Alquarashi; Bothina Hamad

doi:10.3390/ma15093128

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arXiv · 2203.11858

Lattice Dynamics, Mechanical Properties, Electronic Structure and Magnetic Properties of Equiatomic Quaternary Heusler Alloys CrTiCoZ (Z =Al,Si) using first principles calculations

Eesha Andharia·Hind Alquarashi·Bothina Hamad

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Abstract

First principles calculations are performed to investigate the thermodynamical stability, dynamical, mechanical, electronic and magnetic properties of CrTiCoZ (Z= Al/Si) novel quaternary Heusler alloys. Y-type III atomic configuration is found to be the most stable structure for both compounds. The melting temperatures of both compounds are as high as 2142 K and 2420 K for CrTiCoAl and CrTiCoSi, respectively. The electronic structure calculations using GGA-PBE approach show a half metallic behavior of CrTiCoAl. The spin-down channel exhibits a direct band gap of 0.15 eV, whereas the spin-up channel is metallic making CrTiCoAl a half metallic ferromagnet with 100% spin polarization and an appreciable magnetic moment of -2 Bohr Magnetons. The Curie temperature of CrTiCoAl is well above the room temperature (385K), whereas that of CrTiCoSi is below the room temperature (203K).

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Eesha Andharia, Hind Alquarashi, Bothina Hamad. 2022-03-22. Lattice Dynamics, Mechanical Properties, Electronic Structure and Magnetic Properties of Equiatomic Quaternary Heusler Alloys CrTiCoZ (Z =Al,Si) using first principles calculations. https://doi.org/10.3390/ma15093128

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