Multifunctional potential of SrMoN 3 nitride perovskite: A DFT study of structural, optical, electronic, thermoelectric, phonon, thermodynamic and mechanical properties

The nitride perovskite SrMoN 3 shows a combination of structural stability, semiconducting behavior and mechanical anisotropy, as demonstrated by comprehensive first-principles calculations. SrMoN 3 forms a stable monoclinic perovskite structure with a Goldschmidt tolerance factor of approximately 1.0 and no imaginary phonon modes, confirming both dynamic and structural stability. Charge density and electron localization function analyses indicate mixed ionic–covalent bonding, with ionic Sr–N interactions and strong covalent Mo–N bonds. Additionally, spin-density calculations suggest possible antiferromagnetic ordering. Electronic structure studies reveal a narrow indirect bandgap with highly hybridized N 2p–Mo 4d valence states, implying anisotropic electron–hole transport and enhanced n-type conductivity when doped. Thermoelectric calculations predict high carrier mobility, bipolar transport and highly efficient electron-mediated heat conduction. Optical analyses show strong ultraviolet absorption, a high refractive index and tunable plasmonic behavior upon doping. Elastic constants meet the Born stability criteria, displaying moderate stiffness, significant anisotropy and auxetic behavior in certain directions, which facilitates direction-dependent mechanical responses. Vibrational and thermodynamic analyses verify stability at elevated temperatures. These results position SrMoN 3 as a versatile material: a stable nitride perovskite with excellent optical absorption, notable thermoelectric performance and highly anisotropic elasticity, making it suitable for next-generation photovoltaic, thermoelectric power generation, plasmonic devices and mechanically adaptive systems.