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We have performed ab initio investigation of some physical properties of the perovskite TlMnX3 (X = F, Cl) compounds using the full-potential linearized augmented plane wave (FP-LAPW) method. The generalized gradient approximation (GGA) is employed as exchange-correlation potential. The calculated lattice constant and bulk modulus agree with previous studies. Both compounds are found to be elastically stable. TlMnF3 and TlMnCl3 are classified as anisotropic and ductile compounds. The calculations of the band structure of the studied compounds showed the semiconductor behavior with the indirect (M–X) energy gap. Both compounds are classified as a ferromagnetic due to the integer value of the total magnetic moment of the compounds. The different optical spectra are calculated from the real and the imaginary parts of the dielectric function and connected to the electronic structure of the compounds. The static refractive index [Formula: see text] is inversely proportional to the energy bandgap of the two compounds. Beneficial optics technology applications are predicted based on the optical spectra.

A theoretical comprehensive implementing of the structural, elastic, electronic and optical properties of CsSnX3 (X = Br and I) perovskite compounds under pressures 0 and 20 GPa is performed by ab-initio calculations included within the density functional theory (DFT). The structure of crystal perovskite compounds is found to be stable under induced pressure. The compounds have shown a decrease in the structural properties such as lattice constant and interatomic bond length when the pressure was induced. Whereas, there was an increase in the thermodynamic properties such as Debye temperature and average velocities of sound when pressure was induced. Moreover, the values of mechanical parameters, such as the elastic constant, increased under applied pressure. The electronic parameters indicate that the compounds can be classified as semiconductor materials with a direct (M-M) gap. The induced pressure is found to enhance the optical parameters in the different energy regions. Our calculation predicts that the studied compounds can be the relevant candidates in optical, thermoelectric and mechanical applications.

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In this work, structural, thermal, electro-magnetic and thermoelectric attributes of CoNb1−xTixSn (x  =  0, 0.75, 0.5, 0.25, 0) alloys have been investigated using density functional theory (DFT). The structural reforms, brought to CoNbSn, portray the increase in its rigidity when increasing the Ti content substituted at the Nb site. They also remodel the character of the alloy from semiconducting paramagnetic to half-metallic ferromagnetic nature. By investigating elastic properties that are interlinked with structural optimizations and enthalpy of formation, studied alloys displayed stable structure. Thermoelectric properties such as Seebeck coefficient (S), electrical conductivity (σ/τ) and power factor (S2 σ/τ), are calculated based on the Boltzmann transport theory. Results revealed that for x  =  0.75 in CoNb1−xTixSn, a temperature dependent switch from n-type to p-type is observed. According to the results obtained, CoNb1−xTixSn alloys could have potential thermoelectric applications.

In this theoretical work, we perform an investigation to study the influence of V doping in LaFeO 3 (LFO). For V doping, the opted Fe site shows remarkable modifications in the inherited attributes of pristine LFO. We use formation energies and optimizations to explore the ground state structural stability. Electronic properties of stable structures reveal large spin polarization effects with spin-up (metallic) and spin-down (semiconducting) configurations. We observe the highest ferromagnetism for V-25% doping which is a suitable candidate for application in magnetic tunnel junctions.Optical analysis reveals that the studied materials are highly transparent under incident light. All thermoelectric results suggest that the compounds can be categorized as p-type doping. The thermoelectric parameters predict that the present compounds have beneficial thermoelectric industrial applications, especially V 0.25 -LFO and V 0.5 -LFO. We expect that these compounds are suitable functional materials for novel magnetic or spintronic devices and as transparent conducting materials.

First-principle calculations are performed using DFT as implemented in Wien2k code to compute the mechanical, electronic, optical and thermoelectric properties of NiYSn (Y = Zr and Hf) alloys. The computed lattice constants, bulk modulus and cohesive energy of these alloys at 0 K and 0 GPa are performed. NiZrSn and NiHfSn are found to be anisotropic and elastically stable. Furthermore, both alloys are confirmed to be thermodynamically stable by the calculated values of the standard enthalpy of formation. The Young’s and shear moduli values show that NiZrSn seems to be stiffer than NiHfSn. The optical properties are performed using the dielectric function. Some beneficial optoelectronic applications are found as exposed in the optical spectra. Moreover, the alloys are classified as good insulators for solar heating. The thermoelectric properties as a function of temperature are computed utilizing BoltzTrap code. The major charge carriers are found to be electrons and the alloys are classified as [Formula: see text]-type doping alloys.