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Spintronics is a rapidly developing field in advanced technology. It focuses on manipulating the spin of electrons to achieve high-speed data transfer, handling, and storage in order to enhance its capabilities. We conducted a systematic investigation of the ferromagnetism, electronic, and thermoelectric characteristics of spinel compounds LiFe 2 (O/S) 4. Our analysis for optimization demonstrates that ferromagnetic states exhibit great energy release compared to the antiferromagnetic states, indicating the presence of ferromagnetic behavior in the studied compounds. To evaluate the presence of ferromagnetism above room temperature, we employ the Heisenberg model to calculate the Curie temperature and spin polarization to evaluate the presence of ferromagnetism above room temperature. Additionally, a concise overview of the nature of ferromagnetism, including band structures, density of states, exchange energies and constants, hybridization double exchange model, and crystal-field energy, is provided in this research. The absorption of a shift in magnetic moment from Fe to the Li and O/S sites suggests that the ferromagnetic behavior is primarily due to the spin of electrons. Furthermore, we explore the impact of the thermal parameters on the electro-spin as well as the thermoelectric characteristics for both spin-down and spin-up states, providing insights into the energy-harvesting potential. • Half-metallic ferromagentic spinels LiFe 2 (O/S) 4. • Elastic constant are investigated for structural stability. • Electronic and magnetic properties for spintronic applications. • Magnetic moments are discussed for both compounds. • The electronic and lattice thermal conductivity are calculated for thermoelectric characteristics. [ABSTRACT FROM AUTHOR]

Methods based on density functional theory are used to evaluate the thermodynamic, mechanical, optoelectronic and thermoelectric properties of the alkali metal-based iodides: XGeI 3 (X = K, Rb and Cs). The thermodynamic stability of these compounds is checked by negative formation energy, and mechanical stability tested through tensor analysis of Chapin's method. For optoelectronic and thermoelectric properties, the recently developed modified Becke–Johnson potential is applied for accurate analysis of bandgap values. The optical properties are explored in terms of dielectric constants and refraction, while thermoelectric properties are explained by electrical and thermal conductivities, Seebeck coefficient, power factor and figure of merit scale. The narrow bandgap, high value of light absorption in the visible region and thermoelectric efficiency make XGeI 3 prospective materials for renewable energy applications. • We elucidate physical properties of alkali metal-based iodides [XGeI 3 (X = K, Rb, and Cs)]. • We confirm thermodynamic stability of studied compounds by enthalpy of formation. • Thermoelectric properties of spinel oxides determined using BoltzTraP code. • Narrow bandgap and thermoelectric efficiency give XGeI 3 potential in renewable energy applications. • These materials are suitable for use in thermoelectric devices. [ABSTRACT FROM AUTHOR]

Abstract: We report a systematic study of the structural, electronic and magnetic properties of Cr-doped CdTe for various Cr concentrations x (=0.25, 0.5, 0.75 and 1.0) using first principles calculations based on the density functional theory (DFT). The electronic band structure of the alloy has been calculated using the Wu–Cohen (WC) as well as the Angel-Vosko (EV) generalized gradient approximation (GGA) for the exchange-correlation potential. The analysis of the density of states (DOS) curves shows the half-metallic ferromagnetic character with half-metallic gap more than 0.52eV. While the origin of half-metallic ferromagnetism is explained, the band structure calculations are used to determine s (p)–d exchange constants N 0 α (conduction band) and N 0 β (valence band) that agree with typical magneto-optical experiment. It is found that the p–d hybridization reduces the magnetic moment of Cr from its free space charge value and produces small magnetic moments on the Cd and Te sites. Lastly, we discuss the robustness of half-metallicity with respect to the variation of lattice constants of the Cr x Cd1−x Te alloys. [Copyright &y& Elsevier]

Using the full-potential linearized augmented plane wave plus local orbitals method within the frame work of density functional theory, the Sc-based double halide perovskites K 2 ScAgZ 6 (Z = Cl, Br, I) are investigated for determining their physical properties. To investigate the structural and thermodynamic stability of these Sc-based double halide perovskites we calculate tolerance factor, formation energy, and phonon dispersion curve using GGA-PBEsol approximation. The calculated values of lattice parameters using GGA-PBEsol are found to be consistent with the available data. Subsequently, the Tran-Blaha modified Becke-Johnson (mBJ-LDA) potential is used for electronic properties. Implementation of TB-mBJ potential is clearly shows that K 2 ScAgZ 6 have indirect bandgap, which is consistent with the literature. To evaluate these double perovskites and reveal their potential use in optical devices, several optical parameters are computed for an incident photon energy range of 0–8 eV. The BoltzTraP code is also employed to investigate temperature dependent electrical characteristic of these compounds in the temperature range of 200–600 K. Investigated halide double-perovskites have been shown to display excellent physical properties for solar cells and renewable energy device applications. • In the cubic phase double perovskites are structurally and thermodynamically stable. • The calculated indirect bandgaps for K 2 ScAgCl 6 , K 2 ScAgBr 6 , and K 2 ScAgI 6 are 2.0, 1.85, and 1.65 eV. • These are suitable materials for solar cell devices due to their greatest least reflection, absorption, and optical loss in the visible area. [ABSTRACT FROM AUTHOR]

Spintronics is an emerging field that has the potential to replace conventional electronics due to their comparatively high speed, low power consumption, and infinite endurance. The phenomena of ferromagnetism with high spin polarization in double perovskites make them the desired materials for spintronics. In the present work, the structure of Cs 2 CuCrX 6 (X = Cl and Br) and their magnetic and optoelectronic properties were studied by utilizing density functional theory (DFT). For the calculations of exchange-correlation potential, PBE-sol approximation was utilized while for the accurate measurement of electronic band structure and density of states (DOS), we employed mBJ potential. Both materials exhibit cubic structure and are thermodynamically stable as confirmed by volume optimization and negative formation energy respectively. Spin-based energy-volume optimization and values of exchange constants reveal the ferromagnetic nature of materials. It has been observed that 3-d states of Cr are responsible for ferromagnetism and have the major contribution to the net magnetic moment caused by exchange splitting. Furthermore, investigations of band structure and electronic density of states showed that both Cs 2 CuCrCl 6 and Cs 2 CuCrBr 6 were indirect bandgap (E g) semiconductors with the E g values of 1.2 eV and 0.33 eV respectively. The optical spectra of materials showed strong absorption in the ultraviolet region. Lastly, the transport and thermoelectric properties (TE) of materials were investigated in the range of temperature 300 K–800 K by using the BoltzTrap code. The transport parameter which included the electrical conductivity (σ/τ) and thermal conductivity (κ e /τ) of the materials showed a decreasing trend with temperature whereas the Seebeck coefficient (S) and Power factor (P.F) showed an increasing trend for Cs 2 CuCrCl 6 while decreases in case of Cs 2 CuCrBr 6. Furthermore, a high figure of merit (ZT) with values of 0.75 and 0.64 was obtained for Cs 2 CuCrCl 6 and Cs 2 CuCrBr 6 respectively. The results of this work are encouraging and show the capabilities of the discussed materials in the fields of spintronics, thermoelectric, and optoelectronics. [Display omitted] • This manuscript presents a comprehensive theoretical investigation into the magnetic, optoelectronic, and thermoelectric properties of Cs 2 CuCrX 6 (X = Cl and Br) double perovskites. • Through rigorous theoretical analysis, the manuscript unveils the spintronic potential of Cs 2 CuCrX 6 double perovskites, shedding light on their intrinsic magnetic properties and their suitability for spin-based electronic applications. This insight opens avenues for innovative spintronics device designs. • Delving into the optoelectronic characteristics, the manuscript elucidates the optical properties of Cs 2 CuCrX 6 double perovskites, offering valuable insights into their light-matter interaction mechanisms. • By examining the thermoelectric properties of Cs 2 CuCrX 6 double perovskites, the manuscript assesses their potential for thermoelectric applications, highlighting their ability to efficiently convert heat into electrical energy. This exploration paves the way for dual-functionality devices coupling data storage with energy harvesting capabilities. [ABSTRACT FROM AUTHOR]