1T’-[formula omitted] hybrid monolayer as a novel magnetic material: A first principles study

Abstract

The advent of two-dimensional (2D) materials, such as transition metal dichalcogenides (2D-TMD), has led to an extensive amount of interest amongst scientists and engineers alike in search of major breakthroughs in the electronic, magnetic, and thermodynamic properties of 2D materials, generating interest in novel device applications. This paper discusses a theoretical study of the structural, electronic, magnetic, stability, phonon dispersion, and thermodynamic properties of the monoclinic RuWTe2 monolayer, a type of TMD in its 1T’ phase. The study uses computational modeling, employing the Density Functional Theory (DFT) and Density Functional Perturbation Theory (DFPT) formalisms, using GGA approximation and pseudopotentials to replace nucleus electrons in each atomic species. Just for bandgap estimation, it was used a single point energy of HSE06 hybrid functional which resulted in a small gap semiconductor (≈ 0.4eV). Even after adding the DFT+U correction to PBE functional, it presented magnetic properties with a trend toward ferrimagnetism. It presents structural and energetic stability through calculations of cohesive, formation energy, and phonon dispersion, since it does not present virtual phonon frequency. Through thermodynamics, the free energy (F) indicates that the synthesis process for 1T’-RuWTe2 would be spontaneous even at low temperatures. These results demonstrate that the monoclinic 1T’-RuWTe2 hybrid monolayer is a promising candidate suitable for applications in magnetic and thermal devices.