Probing the electronic structure, optical, and transport nature of lanthanide-based ternary materials: A First-principles perspective

Abstract

High thermal stability and adjustable optoelectronic properties are the unique characteristics of lanthanide-based materials. The complex interplay between unique electronic, optical, and thermoelectric characteristics of lanthanide-based ternary chalcogenides is investigated by first principles modeling. The cohesive energy values were anticipated to be −4.54 eV/atom for PrSF and −4.87 eV/atom for PrSBr suggesting PrSBr to have the greatest bonding properties and is the most stable material. The computed formation energies range from −1.3 to −3.0 (eV/f. u), demonstrating their stability. The inclusion of bromine, a more electronegative element than fluorine, produces unique hybridization patterns and spin polarization effects. Compared to PrSBr, PrSF bonding employs more effective orbital hybridization, resulting in a greater band gap. PrSF has a higher frequency dielectric constant compared to PrSBr. The absorption edges in the ε2(ω) result from optical transitions between the Pr-f, S-p, F-p, and Br-p states. As the temperature rises, the Seeback coefficients for PrSF and PrSBr decrease exponentially. The thermal conductivity spectra of PrSF and PrSBr materials exhibit a linear increase across the temperature range. As temperature rises, the concentration of carriers and mobility increases, resulting in increased electrical conductivity values.