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To understand the influence of doping Sr atoms on the structural, magnetic, and electronic properties of the infinite-layer NdSrNiO2, we carried out the screened hybrid density functional study on the Nd9-nSrnNi9O18 (n = 0–2) unit cells. Geometries, substitution energies, magnetic moments, spin densities, atom- and lm-projected partial density of states (PDOS), spin-polarized band structures, and the average Bader charges were studied. It showed that the total magnetic moments of the Nd9Ni9O18 and Nd8SrNi9O18 unit cells are 37.4 and 24.9 emu g−1, respectively. They are decreased to 12.6 and 4.2 emu g−1 for the Nd7Sr2Ni9O18-Dia and Nd7Sr2Ni9O18-Par unit cells. The spin density distributions demonstrated that magnetic disordering of the Ni atoms results in the magnetism decrease. The spin-polarized band structures indicated that the symmetry of the spin-up and spin-down energy bands around the Fermi levels also influence the total magnetic moments. Atom- and lm-projected PDOS as well as the band structures revealed that Ni (d x 2 − y 2 ) is the main orbital intersecting the Fermi level. As a whole, electrons of Sr atoms tend to locate locally and hybridize weakly with the O atoms. They primarily help to build the infinite-layer structures, and influence the electronic structure near the Fermi level indirectly. [ABSTRACT FROM AUTHOR]

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]

Abstract: The structure, stability and electronic properties of the different B-site partial substituted derivatives LaNi4.5M0.5 (M=Al, Mn, Fe, Co) have been investigated by means of the density functional theory using the full-potential linearized augmented plane wave (FLAPW) method with the generalized gradient approximation (GGA). The optimized results indicate that all of Al, Mn, Fe, Co atoms prefer to substitute Ni atoms in the 3g sites. Due to the different radius of elements, the cell volume would increase with the doping Ni (3g) atoms. And the sequence of volume is LaNi4.5Al0.5 >LaNi4.5Mn0.5 >LaNi4.5Fe0.5 >LaNi4.5Co0.5 >LaNi5, which is in agreement with the experimental result. The calculated data of formation and cohesive energies indicate that LaNi4.5Mn0.5 has the stablest structure among five alloys. Based on the analysis of the density of states and charge density, the interactions of Mn–Ni, Fe–Ni, Co–Ni atoms are greatly stronger compared to the Ni–Ni interaction, while the interaction of Al–Ni atoms is weakened. Based on the formation energy of hydrogen atom in LaNi4.5M0.5H0.5, the sequence of bounding hydrogen atoms is LaNi4.5Mn0.5 >LaNi4.5Fe0.5 >LaNi4.5Co0.5 >LaNi4.5Al0.5 >LaNi5. [Copyright &y& Elsevier]