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The density functional theory (DFT) is used to investigate the geometries, relative stabilities, electronic properties and natural population analysis for small neutral, anionic, and cationic indium clusters. From 2D to 3D structures of the neutral, anionic, and cationic indium clusters are studied. The optimized results indicate that the geometries of the anionic and cationic indium clusters exhibit large similarities from those of neutral indium. According to the calculations of the averaged binding energy, fragmentation energy, and second-order energy difference, we estimate the relative stabilities of In n (0,±1) clusters. Odd–even alterations are found in the adiabatic electron affinity (AEA), vertical electron detachment energy (VDE), adiabatic ionization potential energy (AIP), and vertical ionization potential energy (VIP) for the neutral, anionic, and cationic indium clusters. In 14 has the highest AEA, In 10 has the highest VDE, In 13 has the highest AIP, and In 5 has the highest VIP. The HOMO–LUMO gaps are also calculated for the In n (0,±1) clusters to investigate their electronic properties. Natural population analysis reveals that the sign of the charge are zero for In n clusters, In n − clusters occupy the negative charges and In n + clusters occupy the positive charges. [ABSTRACT FROM AUTHOR]

We report a computational study of the aluminum doped germanium clusters Ge n Al ( n = 1–9). The molecular geometries and electronic structures of the Ge n Al clusters are investigated systematically using quantum calculations at the B3LYP level with the 6-311G(d) basis sets. The growth pattern behaviors, stabilities, electronic properties, and magnetic moments of these clusters are discussed in detail. Obviously different growth patterns appear between small and larger Al-doped germanium clusters, the optimized equilibrium geometries trend to prefer the close-packed configurations for Al-doped germanium clusters up to n = 9. The size dependence of cluster average binding energies per atom ( E b /atom), second-order differences of total energies ( Δ 2 E ), fragmentation energies ( E f ) and HOMO–LUMO gaps of Ge n +1 and Ge n Al ( n = 1–9) clusters are studied. The stability results show that Ge n +1 cluster possess relatively higher stability than Ge n Al cluster. Furthermore, the investigated highest occupied molecular orbital-lowest unoccupied molecular orbital gaps indicate that the Ge n +1 and Ge n Al clusters have different HOMO–LUMO gap. In addition, the calculated vertical ionization potentials and vertical electron affinities confirm the electric properties of Ge n +1 and Ge n Al clusters. Besides, the doping of Al atom also brings the decrease as the cluster sizes increase for atomic magnetic moments ( μ b ). [ABSTRACT FROM AUTHOR]

The Geometries, relative stabilities, and electronic properties of the most stable host Ga n +1 and doped Ga n Ti (0, ±1) ( n = 1–10) clusters are studied using density functional theory (DFT) with valence basis set LANL2DZ. We determine the equilibrium geometries of host Ga n +1 and doped Ga n Ti( 0, ±1) ( n = 1–10) clusters by optimizing the bond length and bond angle of various structural isomers. With increasing cluster size, the Ga n Ti (0, ±1) clusters tend to adopt compact structures, and the ground state structures of Ga n Ti ±1 keep the similar geometric structure as the Ga n Ti clusters. When the number of Ga atom is even, the natural population analysis of Ga n Ti − clusters possess high charges transfer. In order to study the stability of cluster, the average binding energies per atom ( E b /atom), fragmentation energies ( E f ), second-order differences of total energies (Δ 2 E ) of host Ga n +1 and doped Ga n Ti (0, ±1) ( n = 1–10) clusters are studied. The calculation results of fragmentation energies of Ga n +1 clusters present a leaping odd–even oscillatory behavior from n = 1 to n = 10. Furthermore, the calculated HOMO–LUMO gaps of Ga n Ti clusters are distinctly higher than those of Ga n +1 clusters, except for Ga 3 Ti clusters. The size dependence of cluster’s vertical electron detachment energies (VDE), adiabatic electron affinities (AEA), and adiabatic ionization potentials (AIP), vertical ionization potentials (VIP) are discussed. [ABSTRACT FROM AUTHOR]

Two-Dimensional carbon-based materials as a potential hydrogen storage medium have attracted great attention. In this study, various key aspects such as structure, electronic properties, stability, and hydrogen storage performance of Na-modified Irida-Graphene (IG) were thoroughly investigated using density functional theory (DFT) calculation methods. The calculation results show that the binding energy of Na atoms with the substrate is 1.51 eV, far exceeding the cohesive energy. The AIMD results reflect the good thermal stability of the model. One Na atom can adsorb up to 5H 2 molecules. The IG loaded with eight Na atoms on both sides can adsorb 32H 2 molecules, achieving a hydrogen storage capacity of 7.82 wt % , far exceeding the US DOE target of 5.5 wt %. The calculated Van 't Hoff equation indicates a desorption temperature of 248 K for the model. Moreover, reversible hydrogen storage can be achieved at medium to low pressures, with desorption temperatures ranging from 285 K to 417 K. These results suggest that Na-Modified IG models are candidate materials for reversible hydrogen storage under near-ambient conditions. [Display omitted] • Sodium modification of Irida-Graphene enhances its hydrogen adsorption capacity. • The interaction between IG-Na and H 2 was analyzed using the IGMH method. • The hydrogen storage capacity of IG-Na medium reaches 7.82%. [ABSTRACT FROM AUTHOR]

The atomic structures, stabilities, electronic structures, and magnetic moments of neutral and singly positively and negatively charged SnnAl (n = 1–10) clusters are calculated with B3LYP/SDD method in density functional theory. Detailed analyses are implemented to acquire the properties of SnnAl(0, ±1) clusters, such as relative stabilities, electronic properties, natural population analyses, and magnetic moments. The calculation results show that the ground‐state structures of Sn2Al, Sn7Al, and Sn8Al clusters are different from those of Sn3, Sn8, and Sn9 clusters, the variation trend of binding energies of Snn + 1 and SnnAl(0, ±1) coincides, and the small kinks are the same. It is found that the changing tendency of the vertical electron detachment energies (VDEs) of Snn + 1 and SnnAl(0, ±1) is almost consistent with that of the adiabatic electron affinities (AEAs), except Sn8Al. Furthermore, the adiabatic ionization potential energies (AIPs) of SnnAl and Snn + 1 clusters exhibit oscillatory behavior, but the variation trend of SnnAl is contrary to that of Snn + 1 from n = 1 to n = 7. The simulation results indicate that SnnAl− and SnnAl+ display a similarity in the magnetic moments, when n = 1, 3, 4, 5, 6, 7, and 9. The charges are transferred from Al to Sn in Sn1–4Al. [ABSTRACT FROM AUTHOR]

Al17 clusters exhibit apparent changes in curvature, which resemble macroscopic metal tips. Here, we show, using the density functional theory method, how surface charges of Al17q (q = −2 to +3) ions affect the adsorption and dissociation behavior of HCl molecules. Geometries, adsorption energies, vibrational frequencies, Mulliken population analysis and transition states of (Al17HCl)q (q = −2 to +3) adsorption complexes were studied. The results revealed that HCl molecules tend to locate on tip sites of the Al17q (q = −2 to +3) ions. Anionic adsorption complexes are prone to H affinity adsorption, whereas cationic adsorption complexes favor Cl-affinity adsorptions. These adsorption behaviors look quite like macroscopic tip effects. H–Cl bonds of the adsorption complexes weaken with an increase in either positive or negative charge. Dissociation barriers of the H–Cl bonds exhibit binding energies that are 2 orders of magnitude smaller than those of an isolated HCl molecule. Considering adsorption energies and dissociation barriers comprehensively, HCl molecules should dissociate spontaneously for all the models considered. Generally, the more negative charges the clusters carry, the more energy the reaction will release. [ABSTRACT FROM AUTHOR]