New noncentrosymmetric rare-earth metal gallium thioantimonates, Ln(4)GaSbS(9) were synthesized from stoichiometric element mixtures at 950 °C by high-temperature solid-state reactions. These compounds crystallize in orthorhombic space group Aba2 (no.41) with a = 13.799(3)-13.427(5) Å, b = 14.187(3)-13.756(5) Å, c = 14.323(3)-13.954(5) Å, V = 2804(2)-2577 (2) Å(3), and Z = 8 on going from Ln = Pr to Ho. The asymmetric building units, bimetallic polar (Sb(2)S(5)) units, and dimeric (GaS(4))(2) tetrahedra are in-phase aligned as an infinite single anionic chain of {[(Ga(2)S(6))(Sb(2)S(5))](10-)}(∞) that is further packed in a noncentrosymmetric pseudolayer motif perpendicular to the c axis. Three of the title compounds show large powder second harmonic generation (SHG) effects at 2.05 μm, and two of them also exhibit large transparency ranges (1.75 or 0.75 to 25 μm) in the middle-IR region. Significantly, the Sm-member exhibits the strongest SHG response among sulfides to date with intensity approximately 3.8 times that of the benchmark AgGaS(2). The band structures, indirect band gap nature, bonding strengths, and lone pair effects around Sb have also been studied by Vienna ab initio simulation package calculations.

Uniform hexagonal Cu2S nanowires with 2-6 nm diameters, 0.1 to several mum in length, were made by precipitation and thermolysis at 155 degrees C for 120 min from a Cu-thiolate colloid with a viscosity of 93.5 mPa/s. The morphologies of the final nanoproducts are governable through control of the coordination chemistry of Cu ions and thiols and the association of the Cu/S fragments. The evolution of nanowires, with the polymerization and heating temperature, and the parameters affecting the viscosity of the colloid precursor are reported.

Uniform Bi 2 S 3 nanorods growing along [001] have been synthesized from the precursor of Bi[S 2 CN(C 8 H 17 ) 2 ] 3 by two different approaches: solventless and solvothermal methods. The structure, morphology, and formation process of the nanorods have been investigated by SEM, TEM, HRTEM, XRD, and EDX analyses. The growth direction is intrinsically governed by the crystal structure motif and the high surface energy of the (001) plane of orthorhombic Bi 2 S 3 according to the CASTEP calculations. Besides, some important factors that influence the growth of Bi 2 S 3 nanorods, such as the length of alkyl group in the precursor and the reaction temperature are investigated. The optical band gap of the as-synthesized Bi 2 S 3 nanorods is measured to be 1.50 eV indicating a slightly blue shift owing to the quantum size effect.