First Principles Simulation of Ferromagnetic A2MnCl6 (A = K, Rb, Cs) Double Perovskites for Energy Efficient Spintronic Applications

First Principles Simulation of Ferromagnetic A2MnCl6

Abstract

Double perovskites are emerging due to their eco-friendly, and spin-polarized characteristics, and present an appealing option for applications in spintronics. In current investigation, we delve into the effect of Mn d-electrons on the magnetic response of A2MnCl6 (A = K, Rb, Cs) through theoretical analysis using the WIEN2k code. The value of lattice constant increased from 9.61 to 9.69 and 9.82 Å when K is replaced with Rb and Cs respectively which caused a reduction in Bulk modulus from 39.91 to 39.29 and 38.71 GPa. The calculated formation energy values (-1.64, -1.82, and -1.96 eV) affirm the thermodynamic stability of the system. Examination of band structure and density of states divulges a half-metallic ferromagnetic character, elucidated through exchange energies and exchange constants. Our calculations indicate that the interplay of basic hybridization processes, exchange energies and crystal field effects play a pivotal role in the development of ferromagnetism driven by the spin of electrons. Finally, an assessment of electrical (0.2-1.02x1019/Ωms) and thermal conductivity (0-4.8x1014 W/mKs), Seebeck coefficient (>200 µV/K), power factor (0-4.5x1011 W/mK2s), magnetic susceptibility (0-1.6x10-9 m3/mol), and figure of merit (up to 0.97) is performed to evaluate the prospective of the inspected compounds for potential applications in energy harvesting technologies.