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In this paper, a combination of DFT study and Monte Carlo (MC) simulations has been performed on Gd compound which undergoes a second–order phase transition from ferromagnetic state to paramagnetic one. For this single material, the temperature-dependent total magnetization and magnetic susceptibility have been calculated and are revealed that the Curie temperature is acceptable concurrence with the experimental value. Furthermore, it was showed that under an external magnetic field of 2 Tesla (T), MCE of Gd compound around its Curie point in regard to the maximum value of magnetic entropy change ( ), agrees well with the experimental one. Besides, the Relative Cooling Power (RCP) values are found to be 34.37, 69.18, 90.74 and 128 J.kg−1 under different magnetic fields of 0.5, 1.0, 1.5 and 2T, respectively. All findings which are presented here indicate that DFT calculations and Monte Carlo simulations can be efficiently used to predict the magnetic and magnetocaloric features of Gd and related alloys.

Stannous-based perovskite oxide materials are regarded as an important class of transparent conductive oxides for various fields of application. Enhancing the properties of such materials and facilitating the synthesis process are considered major challenging aspects for proper device applications. In the present paper, a comprehensive and detailed study of the properties of spray-coated CaSnO3 thin films onto the Si(100) substrate is reported. In addition, the substrate effect and the incorporation of rare-earth Nd3+ on engineering the characteristics of CaSnO3 thin films annealed at 800 °C are included. X-ray diffraction (XRD) analysis results revealed the orthorhombic structure of all the samples with an expansion of lattice spacing as the substitution of Nd at the Ca site increased. The Raman and FT-IR analysis further confirmed the structural results collected via the XRD analysis. Surface scanning using field-emission scanning electron microscopy revealed the formation of quasi-orthorhombic CaSnO3 grains with an increase in size as dopant content increased. Energy-dispersive X-ray analysis allowed quantification of the elements, while atomic mapping permitted visualizing their distribution along the surfaces. UV–visible spectroscopy and first-principles calculations using density functional theory (DFT) were conducted, and a thorough investigation of the optical and electronic properties of the pure material upon Nd3+ insertion was provided. Electrical properties collected at room temperature revealed a growing conductivity upon doping ratio increase with a simultaneous enhancement in the carrier concentrations and mobility. The findings of the present work will help facilitate the synthesis procedure of large-area stannous-based perovskite oxide thin films through simple and efficient chemical solution methods for optoelectronic device applications.

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In this article we investigate under the same Earth's core conditions, the structural, electronic, and transport properties of Fe-Si-Ni ternary alloys based on Fe and 5% of Si with various concentrations 0%, 15%, 25%, and 40% of element Ni, by means of First-principles calculations. Based on Functional Density Theory (DFT). The Local Density Approximation (LDA) also has been adopted for the potential exchange correlation. We perform the calculation of electronic property at 360 GPa using the software Akai-KKR (machikaneyama), which used the Korringa-Kohn-Rostoker method along with coherent potential approximation (KKR-CPA). Afterward, we calculate the electrical resistivity of impurities formed on the Kubo-Greenwood formula with the vertex correction using SPR-KKR code, which is based on the relativistic polarized spin method. Then, we model the thermal conductivity by electrical resistivity for both varying in the range of 320–360 GPa and 4500-6000k of pressure and temperature, respectively; according to the conditions of the Earth’s inner core ICB using Wiedemann-Franz law. Hence, our results suggest that 85–115 µΩ·cm at 0 K and 320–360 GPa, then 225–285 µΩ·cm at 4500–6000 K and 360 GPa for electrical resistivity, and then 45–55 W·m− 1·K− 1 at 4500–6000 K and 360 GPa of thermal conductivity of Earth’s inner core. Lastly, the thermal and compositional convection is one of the major factors of global magnetic field that is generated by geodynamo driven.