First-principles study of structural, thermodynamic, elastic, and magnetic properties of Cr2GeC under pressure and temperature

The dependences of the structural, thermodynamic, elastic, and magnetic properties of Cr2GeC on pressure and temperature were investigated with the quasiharmonic Debye model and the first-principles method based on the density functional theory. Our calculated data, which were obtained at different pressures and temperatures, are in good agreement with the experimental results. Cr2GeC is mechanically stable in the pressure range of 0-50 GPa and the compressibility along the a axis is greater than along the c axis indicating that the presence of C in the interstitial sites of the Cr octahedra can enhance the stability of the Cr-Ge bonds. It is also found that the antiferromagnetic state is the ground state of Cr2GeC and the total induced magnetic moment of the metastable ferromagnetic state decreases with pressure and completely vanishes at about 25 GPa.