The Implications of Pressure on Electronic, Magnetic, Mechanical, and Elastic Properties of Cobalt and Cobalt Hydride: DFT Calculation

In this paper, we have studied the impact of the pressure on the magnetic, elastic, and mechanical properties of the cobalt Co and cobalt hydride CoH using the full-potential linearized augmented plane wave (FPLAPW) method within the generalized gradient approximation (GGA). The obtained results show an excellent agreement with the available experimental and theoretical data at zero pressure, whereas for pressures up to 20 GPa, the results obtained are considered the first quantitative theoretical prediction for cobalt and cobalt hydride. The calculated electronic properties and spin magnetic moment proved that the metallic and ferromagnetic aspects are preserved for both Co and CoH under different pressure values. Moreover, the results achieved for the elastic constants Cij and the mechanical properties (bulk modulus B, shear modulus G, Young’s modulus Y, and Poisson’s ratio ν) verified that studied systems are mechanically stable under the tested pressure range. Besides, the discussed results reveal the enhancement in the ductility for both Co and CoH with increasing pressure.