First-principles calculations to investigate optoelectronic and thermodynamic properties of new 1T’-RuOsSe2 hybrid monolayer

The electronic band structure, density of states, optical absorption, phonon spectrum, stability, and thermodynamic properties of 1T’-phase RuOsSe2 hybrid monolayer were systematically studied using ab initio calculations based on Density Functional Theory (DFT) and Density Functional Perturbation Theory (DFPT) within the generalized gradient approximation (GGA) and the HSE06 functional of hybrid correlation–exchange. Indirect bandgaps Eg=0.68eV and Eg=1.23eV were obtained within the calculation level GGA-PBE and HSE06. The investigation of optical absorption shows that the RuOsSe2 monolayer exhibits a significant absorption in the ultraviolet and visible regions of the electromagnetic spectrum. Thermodynamic potentials and specific heat at constant volume were calculated, of which dependence on the temperature is discussed. We predict a new RuOsSe2 monolayer from the 1T’ phase that could potentially be synthesized for future electronic devices and bring potential technological applications.