There are many methods and software for simulating materials in practice today, each software or computational method has its own advantages and disadvantages. In the process of studying and researching material simulation, we found that the VASP software combined with the Density Functional Theory (DFT) method is perfect up to this point. Reliability, accuracy, and low resource and time consumption during the calculation process are the standout advantages of this combination. DFT calculations on VASP require the precise construction of input data, including the input files, and it is not necessary to write code to process the output data, which is a significant advantage compared to other methods. Output data is processed through commonly used support software such as Origin and VESTA, which is an advantage of this simulation calculation method.

The structural and electronic properties of sulfur-doped armchair stanene nanoribbons (ASnNRs) have been investigated using Density Functional Theory (DFT). The diverse structural and electronic characteristics induced by the substitution of sulfur atoms were comprehensively analyzed through first-principles calculations, including formation energy, optimized structural parameters, projected density of states (PDOS), and spatial charge density distribution. Various doping configurations were considered by replacing Sn atoms with S at different concentrations and atomic positions, resulting in characteristic doping types such as single-atom doping (top-1S, valley-1S), two-atom doping (ortho, meta, para), and full 1:1 substitution with a 6Sn–6S structure. The results reveal significant changes in the bandgap, increasing slightly from 0.26eV in the pristine state to approximately 0.34eV in the meta configuration, moderately decreasing to 0.15eV in the 100% substitution case, and sharply decreasing in the other configurations. Moreover, most sulfur-doped configurations exhibit non-magnetic behavior similar to pristine ASnNRs, while strong magnetism emerges only in the fully substituted 100% case. These findings demonstrate that sulfur doping can fundamentally modify the electronic and magnetic properties of the material, highlighting its potential application in future spintronic devices.

The paper presents the results of a study on the essential physical properties of armchair SiSn nanoribbon (SiSnNR) material, based on density functional theory (DFT) using the quantum simulation program VASP. Structural parameters are highlighted along with electronic and optical properties. The findings reveal that SiSnNR exhibits significant differences in bond lengths, bond angles, and buckling compared to SiNR and SnNR. SiSnNR demonstrates semiconducting properties, with a direct band gap width of approximately 0.3123Å calculated using GGA-PBE, increasing to 0.5892Å when using the hybrid HSE06 functional. The results indicate that Sn atoms primarily contribute to energy bands below the Fermi level, while Si atoms contribute more to higher energy levels. The study also highlights the overlap of py and pz orbitals, leading to sp2 and sp3 hybridization. In terms of optical properties, the energy range from 3 to 5eV is where SiSnNR exhibits the strongest light absorption. The largest number of electron-hole pairs is generated within the energy range of 8-10eV, resulting in intense optical absorption and transitions in this region.

This study investigates the structural and electronic properties of Au-doped silicene nanoribbons (SiNRs) under the influence of an external electric field of 0.4 eV/Å, utilizing density functional theory (DFT). The stability and structural integrity of SiNRs following Au doping are assessed, considering two distinct doping configurations: the top configuration and the valley configuration, where each unit cell incorporates a single Au atom. The formation energies of the doped systems are calculated to evaluate their thermodynamic stability based on DFT principles. Furthermore, detailed analyses of the density of states (DOS) and energy band structures are conducted. Both doping configurations exhibit metallic characteristics, indicating potential applicability in future nanoelectronic devices.

Investigating the characteristics of the three-step sorption of Sc on armchair silicene nanoribbons is the aim of this study. Since absorbed energy is the largest of the bridge, hollow, valley, and top positions, the hollow position is selected first. The structural state of the second step has an energy of adsorption of 4.18 Å and a bond length of 2.36 Å for Si-Si. Finally, ASiNRs with a high Sc atom had their 1.25 Å surface modified. Adsorbed ASiNRs resulted in new materials with semi-metal and magnetic characteristics, suggesting potential use in spintronic and electronic devices in the future.

In the paper, we investigate the structure and electronic properties of the pristine germanene nanoribbon and four adsorption configurations of 1F and 2F on the substrate of germanene nanoribbon. We obtained the parameters of the most stable structures of pristine germanene nanoribbon and four adsorption configurations. The band structure and the density of state and the part density of state for each element were also obtained. Findings show the adsorption configuration of 1F-GeNR.bridge has no band structure, while other configurations are semimetals with band gap from 0.175eV to 0.67eV; both four adsorption configurations are chemisorption and non-magnetic. The charge distribution of all configurations also was investigated; it showed that there is a charge shift from Ge atoms towards F atoms due to their electronegativity difference.