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The ground‐state structure, average binding energy (Eb), fragmentation energies (ΔE), second‐order difference energy (Δ2E), gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital (HOMO‐LUMO), vertical ionization potential (VIP), vertical electron affinity (VEA), and charge transfer of SnnAln (n = 2–12) clusters are evaluated by density functional theory (DFT). With an increase in the cluster size n, Al atoms aggregate in the geometric center of the cluster, and Sn atoms encapsulate Al atoms in the periphery of the cluster. The variation of ΔE, Δ2E, the HOMO‐LUMO gap, VIP, and VEA of the SnnAln clusters follows similar trends, with certain odd–even oscillations. However, beyond the cluster size n ≥ 9, the HOMO‐LUMO gap decreases significantly, and the VIP and VEA fluctuate significantly, indicating a deterioration of the relative stability of the cluster. Charge transfer proceeds from the Sn atom to the Al atom. This study provides an analysis of the interaction between Sn and Al at the atomic level and explains the segregation phenomenon during the preparation of tin‐aluminum alloys. [ABSTRACT FROM AUTHOR]

Clusters are essential to study the properties of nanomaterials, as they yield interesting molecular and bulk properties with a wide range of applications in nanomaterials. Herein, the ground‐state structure, average binding energy (Eb), fragmentation energy (ΔE), second‐order energy difference (Δ2E), highest occupied molecular orbital and lowest unoccupied molecular orbital (HOMO–LUMO) gap, vertical ionization potential (VIP), vertical electron affinity (VEA), and charge transfer of InnSnn (n = 2–12) clusters are evaluated using density functional theory (DFT). The results show that Sn atoms accumulate and are encapsulated by peripheral In atoms. The Eb of InnSnn clusters is stabilized up to n = 7. The ΔE, Δ2E, HOMO–LUMO gap, VIP, and VEA exhibit pronounced odd–even oscillations, and the changing trends are consistent, indicating that the odd InnSnn clusters are stable. Furthermore, the charge is transferred from the In atoms to the Sn atoms. The charge transfer is observed between the 5s and 5p states of In and Sn atoms, resulting in sp hybridization. The density of states analysis reveals that InnSnn clusters tend to transition from insulators to metals. The magnetic moments of the In and Sn atoms in the odd InnSnn clusters mainly originate from the 5p states. [ABSTRACT FROM AUTHOR]

The formation mechanism and morphology regulation mechanism of tubular ferrous oxalate were investigated by density functional theory. The calculation results showed that the pH value of the reaction solution changed from slightly alkaline to acidic was an important condition for the formation of tubular ferrous oxalate. The size and dispersion of ferrous oxalate can be controlled by introducing Na+ and ethylene glycol (EG) into the reaction system. Guided by theoretical calculations, using sodium oxalate as material to guarantee the initial solution to be slightly basic, while also introducing Na+. Regular tubular ferrous oxalate was successfully obtained by using different ratios of EG and H2O as reaction solution and adjusting pH values at different stages, verified the rationality of the theoretical calculation results. The tubular ferric oxide was obtained by thermal decomposition using tubular ferrous oxalate as the precursor, and the electrochemical performance test results showed that this material is a potential electrode material for supercapacitors. [ABSTRACT FROM AUTHOR]

Herein, AlnTin (n = 2–12) clusters are studied by density‐functional theory method. The evolution of the geometric structure shows that Ti atoms tend to gather inside the clusters. The analysis of the relative stability and highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) gap show that AlnTin (n = 2–12) clusters tend to be stable and the bonding probability increases when n > 8. Nature bond orbitals (NBO) results show that the strong d‐orbital effect between Ti atoms results in the formation of TiTi bonds more easily than AlTi bonds, which leads to the enrichment of Ti atoms inside the AlnTin (n = 2–12) clusters. When n ≥ 8, Al atoms that surround the core formed by Ti atoms tend to form stable triangular configuration, which is stable adsorption site for Al atoms. Herein, the grain‐refining effect of TiAl3 grain refiners in Al alloys at the atomic level can be explained. [ABSTRACT FROM AUTHOR]

Recently, bimetallic clusters have attracted a great deal of attention from research community because clusters yield intriguing properties ranging from the molecular and the bulk materials, which have extensive applications in nanomaterials. Clusters with tailored properties are governed by cluster size, geometrical structures, and elemental composition. Motivated by that we systematically investigated the structural, relative stable, and electronic properties of PbnSbn (n = 2-12) clusters by means of density functional theory. In this paper, the ground state structures, average binding energies, fragmentation energies, HOMO-LUMO gaps, and density of states were theoretically calculated. The results demonstrate that the large clusters adopt distorted ellipsoid structures with no symmetry. The average binding energies tend to be stable when cluster size n ≥ 4. Pb5Sb5 and Pb9Sb9 clusters are more chemically stable compared with the neighboring PbnSbn clusters, which may serve as the cluster assembled materials. The density of states of PbnSbn (n = 2-12) clusters moving toward more negative energy levels with the growing cluster size n, which also becoming more nonlocalized as the clusters size n increasing. [ABSTRACT FROM AUTHOR]

Structure, stability, and dynamics of PbSb ( m + n ≤ 9) clusters were investigated using ab initio molecular dynamics. Size dependence of binding energies, the second-order energy difference of clusters, dissociation energy, HOMO-LUMO gaps, Mayer bond order, and the diffusion coefficient of PbSb clusters were discussed. Results suggest that PbSb, PbSb, and PbSb ( n = 2 or 4) clusters have higher stability than other clusters, which is consistent with previous findings. In case of Pb-Sb alloy, the dynamics results show that PbSb (Pb-22.71 wt pct Sb) can exist in gas phase at 1073 K (800 °C), which reasonably explains the azeotropic phenomenon, and the calculated values are in agreement with the experimental results (Pb-22 wt pct Sb). [ABSTRACT FROM AUTHOR]

In order to investigate the structural and electronic properties of bimetallic Pb n Cu n (n = 2–14) clusters, density functional theory (DFT) were applied. The ground-state structures, average bond distances, binding energies, Mülliken population analysis, vertical ionization potentials, vertical electron affinities, HOMO-LOMO gaps and electronic density of states of Pb n Cu n (n = 2–14) bimetallic clusters were calculated by DFT, The results show that Cu atoms gathering together and encapsulated by peripheral Pb atoms. In addition, the charges always transfer from Pb atoms to Cu atoms, the metallicity of Pb n Cu n clusters increase with the increasing size n, the trend of VIPs is contrary to the trend of VEAs, 4, 8 and 11 are the magic numbers of Pb n Cu n clusters, s-p hybrizations play a crucial role in Pb n Cu n clusters. [ABSTRACT FROM AUTHOR]

• The isomers of Al n V n (n = 2–12) clusters were generated by ab initio molecular dynamics. • The structural evolution and electronic of Al n V n (n = 2–12) clusters were studied. • The centralization of vanadium atoms in aluminum-vanadium clusters is consistent with the experimental fact that aluminum atoms are easy to volatilize in the preparation of aluminum vanadium alloy, and also expound the effect of V on grain refinement in Al-Si alloy, the aggregation of V in Al-V clusters is explained in terms of binding energy and electronic structure in this paper. The structural and electronic properties of Al n V n (n = 2–12) clusters were studied systematically by using density functional theory. With the lowest-energy structures of Al n V n (n = 2–12) clusters that acquired from ab initio molecular dynamics and optimization calculations, the binding energies, vertical ionization potentials (VIP), vertical electron affinities (VEA), the highest occupied molecular orbital-the lowest unoccupied molecular orbital (HOMO-LUMO) gaps and partial density of states (PDOS) were calculated on GGA-BLYP level. The calculation results indicate that vanadium atoms have a tendency of aggregation in the center of Al n V n cluster, and a much stronger binding energy of V 2n clusters than that of Al n V n clusters would be the cause of V atoms aggregate in Al n V n clusters. The PDOS results also show that the binding energy of Al-V bond is much weaker than that of V-V bond due to these two kinds of bonds are bonded in different hybrid ways. This work can not only explain the cause of the poor miscibility between the components of Al-V alloy, but also expound the effect of V on grain refinement in Al-Si alloy. [ABSTRACT FROM AUTHOR]

• A systematic DFT study was carried out to analyze the various Sn–As cluster. • During vacuum distillation, As introduced Sn into the volatiles as AsSn compounds. • The removal As of crude Sn via multistage vacuum distillation. In the realm of high–tech industries, Sn has emerged as an indispensable strategic metal. However, the pyrometallurgical refining process of crude Sn is marred by the production of a substantial amount of hazardous solid waste, notably As–Al slag, posing a direct threat to the ecological safety of the production areas. This study delineates a novel process for the removal of As from crude Sn, employing vacuum gasification–directional condensation, corroborated by theoretical calculations and laboratory experimental research. Theoretically, at a system pressure ranging from 1–10 Pa, the initial volatilization temperatures of Sn and As exhibit significant variance. However, the formation of intermetallic compounds can induce Sn volatilization. Experimentally, the condensation temperature for As was predominantly within 331.7–484.7 K. During the vacuum gasification–directional condensation process, the presence of Sn 4 As 3 intermetallic compounds impeded As volatilization. And under optimal conditions, the As content in the Sn product was recorded at 0.0053 %. Inspired from the calculations, a multistage vacuum distillation method was successfully proposed and achieved to remove As from crude tin. Typically, the total material recovery rate is 99.96 %, and the direct rate of Sn is 93.02 %. The total power consumption and emission of this process are better than the corresponding parameters of other treatment processes, which is a promising solution for the cleaning and effective removal of As. [ABSTRACT FROM AUTHOR]

[Display omitted] • A systematic DFT study was carried out to analyze the various SnAu cluster. • Since NO and CO gases are an increasing health problem, with CO being extremely dangerous as it cannot be detected without a physical detector, the current study offers a very promising way forward towards the research and development of novel sensors for these gases. • Furthermore, DFT is once again shown as a very useful method for the study of physical chemistry of this type, which will undoubtedly motivate and inspire further work in this area. Monitoring and control of CO and NO gases are now considered important for public health. These can be achieved by the research and development of novel sensors. Bimetallic Au–Me clusters such as Au-Pt, Au-Pd, and Au-Pb exhibit extremely high sensitivity, making them suitable for application in gas adsorption and sensing. Here, the ground-state structure, average binding energy, fragmentation energy, second-order energy difference, HOMO–LUMO gap, and average charge of Sn n Au n (n: 2–12) clusters were evaluated using density functional theory calculations. It was found that the Sn n Au n (n = 3, 8) clusters exhibited optimal performance in terms of chemical stability and charge transfer dynamics. Furthermore, the efficiency of CO and NO adsorption on the Sn n Au n (n = 3, 8) clusters was investigated in terms of the geometric, energetic, and electronic properties of the clusters. The results showed that CO and NO molecules chemisorb on the Sn n Au n (n = 3, 8) clusters, thereby allowing limited charge transfer, which significantly affects the physical properties and HOMO–LUMO gap of CO and NO molecules. These results suggest that the Sn n Au n (n = 3, 8) clusters can act as gas adsorbents for CO and NO molecules, and also can be used as effective sensors for NO detection. [ABSTRACT FROM AUTHOR]