Introducing a charge into a solid such as a metal oxide through chemical, electrical, or optical means can dramatically change its chemical or physical properties. To minimize its free energy, a lattice will distort in a material specific way to accommodate (screen) the Coulomb and exchange interactions presented by the excess charge. The carrier-lattice correlation in response to these interactions defines the spatial extent of the perturbing charge and can impart extraordinary physical and chemical properties such as superconductivity and catalytic activity. Here we investigate by experiment and theory the atomically resolved distribution of the excess charge created by a single oxygen atom vacancy and a hydroxyl (OH) impurity defects on rutile TiO(2)(110) surface. Contrary to the conventional model where the charge remains localized at the defect, scanning tunneling microscopy and density functional theory show it to be delocalized over multiple surrounding titanium atoms. The characteristic charge distribution controls the chemical, photocatalytic, and electronic properties of TiO(2) surfaces.

Semiconductor ZnS nanowires were synthesized by a direct templating route in an inverted hexagonal liquid crystal formed by oligo(ethylene oxide)oleyl ether amphiphiles, n-hexane, n-hexanol/i-propanol (2:1), and water. The final product consists of ordered nanowires with a diameter of ca. 5 nm. Most importantly, seven or more close-packed nanowires aggregate to form a regularly shaped bundle with a width of ca. 10−30 nm, duplicating the hexagonal structure of close-packed inverted micelles formed by amphiphiles. We propose a novel simultaneous in situ formation (SISF) technique to synthesize ordered ZnS nanowires by γ-irradiation at room temperature. The reaction is worth noting in that its occurrence is homogeneous and simultaneous. The structures of the inverted hexagonal liquid crystal phase and the final product were characterized by means of polarized optical microscopy (POM), XRD, XPS, TEM and EDX techniques. UV−vis and PL spectra recorded the optical properties of the ZnS nanowires. The amount of amphiphiles passivated with ZnS nanowires is ∼3.4 wt %, as determined by thermal gravimetric analysis (TGA).

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