Structural and elastic investigations of ternary perovskite BaMF3 (M=Ag,Cu) compounds

Abstract

Herein the first-principles modeling within the DFT framework is used to investigate the structural, optoelectronic, elastic, and thermoelectric properties of BaMF3 (M = Ag and Cu) ternary halide Perovskites compounds. The computed tolerance factors for BaAgF3 and BaCuF3 are 0.919 and 0.991 respectively, indicating that the cubic crystal phase of these selected compounds is thermodynamically and mechanically stable. It is found that both the compounds are structurally stable according to the Birch-Murnaghan fit curve for optimization. The IRelast package is used for investigating the elastic properties of both cubic compounds and the findings show that these compounds are mechanically stable, scratch-resistant, ductile, anisotropic, and resistant to plastic deformation. The Trans-Blaha modified Becke-Johnson (TB-mBJ) approximation is employed to determine electronic properties with accuracy and precision. The electronic-band structure analysis depicts a narrow band gap semiconductor nature of BaAgF3 and BaCuF3 compounds which displays indirect band gaps of 0.2 eV for BaAgF3 and 0.3 eV for BaCuF3 at the high symmetrical points from (Γ–M). Furthermore, the computations of total densities of states (TDOS) and partial densities of states (PDOS) are carried out to determine how different states contribute to the various band structures. The optical characteristics of BaAgF3 and BaCuF3 are comprehensively examined in 0-40 eV energy ranges. The selected materials possess high optical conduction and absorption coefficients at the high level of photon energies and show transparency at low incident photon energy ranges. The investigations of optical properties led us to the conclusion that BaAgF3 and BaCuF3 are suitable to use in high-frequency UV devices. The thermoelectric properties show that both materials hold high-power factors, electrical conductivity, and figures of merit (ZT), indicating that they are good thermoelectric materials. This is the first theoretical computational systematic analysis of structural, optoelectronic, elastic, and thermoelectric properties of BaMF3 (M= Ag and Cu) that will be experimentally validated to our knowledge.

First-Principles Calculations to Investigate the Structural, Electronic, Optical, and Elastic Constants; Thermal Conductivity; Raman Scattering; Mulliken Population; and XPS Loss Features of Boron Nitride Polytypes

“…The common version of density functional theory (DFT) is known to underestimate the Kohn–Sham band gap in semiconductors with the local spin density approximation (LSDA), the LSDA + USIC, the spin Perdew–Burke–Ernzerhof generalized gradient approximation (PBE-GGA), the PBE-GGA + USIC, the PBESol, and the PBESol + U . − The electric properties of ternary arsenide Zintl phases are predominantly influenced by the As-p states, as determined by electronic structure calculations. These calculations were performed using the PP-PW method with GGA-PBEsol, which accurately predicted the equilibrium lattice and positional parameters. , The GGA-PBESol + U approximation is used in the research on laves-phase PrFe2 and PrRu2 compounds to address the f states of the Pr atoms and the d states of the Fe and Ru atoms.…”