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We performed first-principles calculations to study the energetics, geometric and electronic properties of zinc sulfide (ZnS) nanostructures. ZnS nanowires (ZnSNWs), nanotubes (ZnSNTs) and nanosheets (ZnSNSs) were considered. Both ZnSNWs and ZnSNTs modeled using hexagonal prisms with the atomic arrangement displaying the characters of wurtzite crystal are more stable than the single-walled ZnS nanotubes presented in previous literature. The energy evolution of ZnSNWs and ZnSNTs as a function of tube diameter and wall thickness was calculated and explained using a simple model. The comparison between the energetics and electronic structures of these ZnS nanostructures was also addressed.

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The first‐principles full potential linearized augmented plane‐wave method within density‐functional theory is used to investigate electronic structure and magnetism of wurtzite (WZ) crystal structure SrC. It is shown that the WZ SrC is a true half‐metallic ferromagnet with a magnetic moment of 2μB per formula unit. The large HM gaps (0.72 eV) and robustness of half‐metallicity with respect to the lattice change make it possible candidate grown epitaxially on appropriate substrates in the form of films thick enough, and therefore should be useful in spintronics and other related applications. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

VGaON center in cubic gallium nitride is a defect complex composing of a substitutional oxygen atom at nitrogen site (ON) and an adjacent gallium vacancy (VGa). Based on first-principles calculations, we predicted that this VGaON center has much in common with the famous nitrogen-vacancy center in diamond, but the excitation energy is very low. The electron spin-polarization of the centers can be tuned by changing the charge states. The neutral ONVGa center has the v↓ and exy↓ states being well isolated from the bulk bands with appropriate spacing which are suitable for achieving spin qubit operation with low excitation energy.

Based on first-principles calculations, we study the electronic structures and magnetic properties of a two-dimensional CdS nanostructure upon hydrogenation adsorption. The results show that the hydrogen atoms can adsorb on Cd atoms within the graphenelike Cd layers with favorable formation energies, and the resulting semihydrogenated CdS systems are expected to show semimetallic properties with Curie temperatures above room temperature. These studies demonstrate that the decoration II-VI group semiconductor with hydrogen might be an efficient route for realizing the interesting long-range ferromagnetism in nanostructure materials.

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