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The paper studies the influence of several factors such as the number of atoms (N), temperature (T), and annealing time (t) on the characteristic quantities of structure, phase transition, and crystallization progress of bulk Au materials using so-called molecular dynamics simulation. The authors hope that obtained results would be very useful for near future experimental research with Au. [ABSTRACT FROM AUTHOR]

Herein, we carefully investigated the Fe3+ doping effects on the structure and electron distribution of Cr2O3 nanoparticles using X-ray diffraction analysis (XRD), maximum entropy method (MEM), and density functional theory (DFT) calculations. We showed that increasing the Fe doping induces an enlargement in the axial ratio of c/a, which is associated with an anisotropic expansion of the unit cell. We found that as Fe3+ replaces Cr in the Cr2O3 lattice, it caused a higher interaction between the metal 3d states and the oxygen 2p states, which led to a slight increase in the Cr/Fe–O1 bond length followed by an opposite effect for the Cr/Fe–O2 bonds. Our results also suggest that the excitations characterize a well-localized bandgap region from occupied Cr d to unoccupied Fe d states. The Cr2O3 and Fe-doped Cr2O3 nanoparticles behave as Mott–Hubbard insulators due to their band gap being in the d−d gap, and Cr 3d orbitals dominate the conduction band. These findings suggest that the magnitude and the character of the electronic density near the O atom bonds in Cr2O3 nanoparticles are modulated by the Cr–Cr distances until its stabilization at the induced quasi-equilibrium of the Cr2O3 lattice when the Fe3+ doping values reaches the saturation level range. [ABSTRACT FROM AUTHOR]

In this research, the structural properties, surface morphology, and magnetic characteristics of nanostructured ternary ferromagnetic alloys grown by a cost‐effective and effortless two‐step electrochemical deposition method on indium tin oxide (ITO) substrates with and without a galvanostatic pretreatment process (GPP) were examined. The GPP was applied at various pretreatment current densities (PCDs) such as −10, −20, and − 30 mA/cm2. The effect of the PCD on the Ni, Co, and Fe contents is found to be insignificant and all resultant Ni‐Co‐Fe thin films show an abnormal co‐deposition. The films have nano‐sized crystallites ranging from 17.3 to 19.6 nm and showed a face‐centered cubic structure with the [111] preferential growth. Compared to the non‐GPP applied Ni‐Co‐Fe film, growing the ternary Ni‐Co‐Fe film on ITO at the PCD of −30 mA/cm2 causes an improvement in the crystal quality and a reduction in the particle size from 150 ± 50 to 70 ± 20 nm. A decrement in the surface roughness and coercivity was also achieved by applying the GPP at the PCD of −30 mA/cm2, but the opposite is true for the GPP performed at the PCD of −10 mA/cm2. The GPP has an effect on the magnetic Squareness Ratio (SQR), but the influence of the PCD on the SQR parameter is negligible. The obtained findings reveal that the properties of the Ni‐Co‐Fe/ITO ternary alloys can be tuned through the GPP applied in various PCDs. Highlights: • The effect of the PCD on the Ni, Co, and Fe contents is found to be insignificant. • The films have nano‐sized crystallites and showed a face‐centered cubic structure with the [111] preferential growth. • The analysis reveals that the GPP changes the crystal quality, Hc parameter, surface roughness, and particle size of the films. • The GPP has an effect on the magnetic squareness ratio (SQR), but the influence of the PCD on the SQR parameter is negligible. • The films had nano‐sized crystallites ranging from 17.3 to 19.6 nm. • The films were ferromagnetic, and the Hc and SQR parameters of the films ranged from 30.2 to 42.7 Oe and from 8.8% to 19.6%. [ABSTRACT FROM AUTHOR]

In this study, molecular dynamics simulations are employed to study the influencing factors such as doping concentration, number of atoms, and temperature on the structural characteristics, phase transition, and crystallization of Fe1-x-yNixCoy alloy. The results show that Fe1-x-yNixCoy alloy always exists with three metals, Fe, Ni, and Cu, which are distributed quite evenly according to the ratio of tap phase concentration. In Fe1-x-yNixCoy alloy, there are always six types of links, Fe–Fe, Fe–Ni, Fe–Co, Ni–Ni, Ni–Co, and Co–Co. Calculated results showed with the increases in the doping concentration, the length of links (r) has a constant value and the height g(r) of the Radial Distribution Function (RDF) has a modified value. The process of increasing the concentration of Fe doping, and reducing the concentration of Co doping leads to an increase in crystallization, a decrease in the size (l) of the alloy, and the total energy of the system (Etot) increases and then decreases. Similarly, increasing the number of atoms leads to an increase in crystallization, but with an increase in temperature, the crystallization process decreases (that corresponds to the change in the number of structural units for the Face-centered cubic (FCC), Hexagonal Close-Packed (HCP), Body-centered cubic (BCC), and Amorphous (Amor)). The obtained results serve as a basis for experimental research in developing new magnetic materials in the future. [ABSTRACT FROM AUTHOR]

This study aims to provide new insights into the influencing factors of the Earth (low temperature, depth, and annealing time) on the heterogeneous kinetics of bulk Fe2O3 by the molecular dynamics simulation method. The obtained results show that there is an influence of the low temperature corresponding to the temperature of liquefied gases, such as helium (4.212 K), nitrogen (77 K), argon (83.8058 K), oxygen (90 K), and carbon (194.5 K), the depth (h) of the Earth's surface from h0 = 0 km to h5* = 6370 km that corresponds to the temperature (T) from T = 300 K to T = 7000 K and the pressure (P) from P = 0 GPa to P = 360 GPa, and then annealing time (t) (120 ps) on the heterogeneous kinetics of bulk Fe2O3, such as the Radial Distribution Function (RDF), Coordination Number (CN), angular distribution, number of structural units, size (l), and energy (E). When the temperature increases in the low temperature (T) region at zero pressure (P), the link length (r), RDF height, size, CN, and the number of structural units FeO4, FeO5, and FeO6 do not change significantly, but only the very large change in E serves as the basis for future research on the mechanical properties and electrical conductivity of semiconductor materials. When the depth (h) of the Earth's surface and the thermal annealing time at different locations are increased, the characteristic quantities of dynamic dynamics change greatly, including the disappearance of FeO4 at depth h1 ≥ 17.5 km and the appearance of additional structural units FeO7, FeO8, and FeO9 at h3 ≥ 1742 km and FeO10 at h5 ≥ 5562.5 km. [ABSTRACT FROM AUTHOR]