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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]

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]

In this paper, the molecular dynamics (MD) method was used to study the influence of factors of bulk Cu material, such as the effect of the number of atoms (N) at temperature (T), T = 300 K, temperature T, and annealing time (t) with Cu5324 on the structure properties, phase transition, and glass temperature Tg of the bulk Cu material. The obtained results showed that the glass transition temperature (Tg) of the bulk Cu material was Tg = 652 K; the length of the link for Cu-Cu had a negligible change; r = 2.475 Å; and four types of structures, FCC, HCP, BCC, Amor, always existed. With increasing the temperature the FCC, HCP, and BCC decrease, and Amorphous (Amor) increases. With an increasing number of atoms and annealing time, the FCC, HCP, and BCC increased, and Amor decreased. The simulated results showed that there was a great influence of factors on the structure found the gradient change, phase transition, and successful determination of the glass temperature point above Tg of the bulk Cu material. On the basis of these results, essential support will be provided for future studies on mechanical, optical, and electronic properties. [ABSTRACT FROM AUTHOR]

This study aims to study the effect of several structural factors, such as number of atoms (N), shell thickness (d), and temperature (T), on the structure of amorphous iron nanoparticle (amorphous nano-Fe) by using the molecular dynamics (MD) method with Sutton–Chen (SC) dip interaction and free boundary conditions. The structural parameters of amorphous nano-Fe include their size (D), energy (E), radial distribution function (RDF), coordination number (CN), and coordination number density (CNd). The results show that the glass temperature ( T g ) and the first peak position (r) of radial distribution function (RDF) have the values of T g = 900 K and r = 2.55 Å, respectively. Furthermore, the values of parameters D and E are always proportional to N−1/3 and N−1, respectively. Regarding the effect of number of atoms, shell thickness, and the temperature on the structure of amorphous nano-Fe, we found that the increase in atoms number leads to decrease in the RDF height and increase in the coordination number (CN). However, increasing temperature leads to decreasing the shell thickness of amorphous nano-Fe. [ABSTRACT FROM AUTHOR]

This paper studies the effect of atoms number (N) of bulk Ag: N = 2 9 1 6 atoms (Ag 2 9 1 6 ), 4000 atoms (Ag 4 0 0 0 ), 5324 atoms (Ag 5 3 2 4) , 6912 atoms (Ag 6 9 1 2) at temperature T = 3 0 0 K, 400 K, 500 K, 600 K, 700 K, 800 K, 900 K, 1000 K on bulk Ag 5 3 2 4 and annealing time t = 200 ps on the structure and phase transition of Ag bulk by Molecular Dynamics (MD) method with Sutton–Chen (SC) pair interaction potential, periodic boundary conditions. The structural results are analyzed through the Radial Distribution Function (RDF), the total energy of the system ( E t o t) , the size (l) , the phase transition (determined by the relationship between E t o t and T), and combined with the Common Neighbors Analysis (CNA) method. The obtained results show that the first peak's position (r) of the RDF has negligible change value, r = 2. 7 8 Å, which is completely consistent with the experimental results. For bulk Ag, there are always four types of structure: FCC, HCP, BCC, Amor and glass transition temperature T g = 5 0 0 K. When decreasing the temperature, bulk Ag changes from liquid state to crystalline state, when increasing the annealing time at T g = 5 0 0 K, bulk Ag changes from amorphous phase to crystalline phase state, leading to the increase of FCC, HCP, BCC structures and the decrease of Amor structure. The obtained results will be used as guide for future experiments. [ABSTRACT FROM AUTHOR]

In this work, we study the effect of atomic number (N) at temperature (T), T = 300 K; effect of T to Al 5324 bulk; effect of annealing time (t) to Al 5324 bulk at crystallization temperature (T g), effect of T g = 600 K on structure, phase transition of Al bulk by Molecular Dynamics (MD) method with embedded Sutton-Chen (SC) potential and recirculating boundary conditions. The results were analyzed through Radial Distribution Function (RDF), total energy of the system (E tot), size (l), Common Neighborhood Analysis (CNA) method, crystallization temperature (T g) (via relationship between E tot , T). The obtained results show that the size (l) of Al bulk is always proportional with atomic number (N) according to the formula l ∼ N−1/3 and the total energy of the system (E tot) always proportional to the number of atoms (N) according to the formula E tot ∼ N−1. In particular, Al bulk always exists in three types of structures, including: Face Centred Cubic (FCC), Hexagonal Close-Packed (HCP), and Amorphous (Amor) structure. When atomic number (N) is increased, the temperature (T) decreases and the tempering time (t) increases then the number units of FCC, HCP increases, Amor decreases leads to change structure and phase transition of Al bulk. • I have studied the effect of atomic number, temperature (T), tempering time (t) on the on the structure of Al bulk. • Determining success crystallization temperature (T g) of Al 5324 bulk is T g = 600 K. • When increasing tempering rate at T = 600 K then first peak position of RDF and structure unit number FCC, HCP increases. [ABSTRACT FROM AUTHOR]

The influence of the concentration of impurity Fe in nanoparticles Ni1−xFex with x = 0.1, 0.3 and 0.5 at T = 300 K; 4000 atoms, 5324 atoms, 6912 atoms and 8788 atoms at T = 300 K; 6912 atoms at T = 1500 K, 1300 K, 1100 K, 900 K, 700 K, 600 K, 500 K and 300 K and tempering time t = 500 ps at 6912 atoms on microstructure, phase transition temperature of Ni1−xFex nanoparticles is studied by molecular dynamics method with the Sutton–Chen embedded interaction potential and liberal boundary conditions. The structural properties are analyzed through the radial distribution function, the energy, the size, the phase transition temperature (determined by the relationship between total energy and temperature) and combined with the common neighbor analysis (CNA) method. The obtained first peak positions of the radial distribution function for the lengths of atomic pair Fe–Fe, Fe–Ni and Ni–Ni are consistent with the experimental data. In Ni1−xFex nanoparticles always exist in three types of structures (FCC, HCP, Amor) and phase transition temperatures range from 500 K to 700 K. When the concentration of impurity Fe in Ni1−xFex nanoparticles increases, then nanoparticles move from crystalline to amorphous state. When Ni1−xFex nanoparticles are at amorphous state, then the influence of factors such as the atomic number, the temperature and the tempering time on structure and transition temperature is negligible. [ABSTRACT FROM AUTHOR]