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We discuss a recent investigation of adatom behavior on the AlSb(001) surface using first-principles electronic structure methods based on the density functional theory. For Al and Sb adatoms, we find a number of novel adatom structures that differ dramatically from previous results for the superficially similar group-III arsenides. In particular, we conclude that it is energetically favorable for an Al adatom to incorporate substitutionally into the outermost layer of the AlSb surface. This observation helps motivate a proposed new reconstruction for the AlSb(001) surface. Finally, we argue that the unusual adatom behavior identified for this surface probably results from the presence of a dimer row composed of a double layer of group-V atoms in the reconstruction, and therefore, it should be generic to all of the antimonides, as well as, the c(4 × 4) reconstruction of the arsenides and phosphides.

Microscopic mechanism of autocatalytic structural transformations of fullerenes is investigated by the action-derived molecular dynamics. Dynamic pathways and the corresponding activation energies are obtained for the Stone-Wales transformation in fullerene and the fullerene coalescence, under the presence of extra carbon atoms. The adatom-assisted Stone-Wales transformation is proved to be a highly probable process unit for the structural transformations and annealing treatments of carbon-based graphitic networks. The complex processes of adatom-assisted fullerene coalescence, yielding very low activation energies, are presented.

We studied the effect of Ni incorporation on the magnetic properties of ${\mathrm{CeSbNi}}_{x}$ $(0l~xl~0.35)$ using resistivity, susceptibility, and magnetization measurements under high pressure and magnetic field. With increasing pressure antiferromagnetic transition temperature ${(T}_{N})$ of CeSb increases continuously leading to a high pressure phase. Similarly, ${T}_{N}$ of ${\mathrm{CeSbNi}}_{x}$ increases with pressure for $xl~0.15$ while increasing pressure weakens a Cr-like anomaly found in the resistivity of ${\mathrm{CeSbNi}}_{0.08}.$ Interestingly, resistivity of ${\mathrm{CeSbNi}}_{0.08}$ under higher pressure becomes very similar to that of CeSb at ambient pressure. Magnetic hysteresis, metamagnetic transition, and saturation behavior, which are absent in the ambient-pressure magnetization of ${\mathrm{CeSbNi}}_{0.05}$ and ${\mathrm{CeSbNi}}_{0.08},$ begin to appear with pressure too. On the other hand, pressure effects in both resistivity and magnetization of ${\mathrm{CeSbNi}}_{0.15}$ and ${\mathrm{CeSbNi}}_{0.35}$ are different from those of ${\mathrm{CeSbNi}}_{0.05}$ and ${\mathrm{CeSbNi}}_{0.08}.$ We discuss these findings with regard to possible Ni-induced changes in the nature of the magnetic interactions of CeSb.

Physical properties of uranium dinitride (UN2) were investigated in detail using first principle calculations based on density functional theory (DFT). To study the strong correlation effects due to 5f uranium valence electrons, the on-site coulomb interaction correction U via the Hubbard-like term (DFT+U) was employed. The UN2 structural, mechanical and thermodynamic properties were calculated within DFT and Various U of DFT+U approach. The Perdew–Burke–Ernzerhof (PBE.5.2) version of the generalized gradient approximation (GGA) is used to describe the exchange-correlation with the projector-augmented wave (PAW) pseudo potentials. A comparative study shows that results are improved by using the Hubbard formalism for a certain U value correction like the structural parameter. For some physical properties the variation versus Hubbard-U is strong like Young modulus but for others it is weakly noticeable such as bulk modulus. 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