Vladimir Kolesnichenko

Bio: Vladimir Kolesnichenko is an academic researcher from University of Iowa. The author has contributed to research in topics: Tungsten & Halide. The author has an hindex of 7, co-authored 13 publications receiving 2845 citations. Previous affiliations of Vladimir Kolesnichenko include University of New Orleans.

Recent advances in the liquid-phase syntheses of inorganic nanoparticles.

Abstract: The development of novel materials is a fundamental focal point of chemical research; and this interest is mandated by advancements in all areas of industry and technology. A good example of the synergism between scientific discovery and technological development is the electronics industry, where discoveries of new semiconducting materials resulted in the evolution from vacuum tubes to diodes and transistors, and eventually to miniature chips. The progression of this technology led to the development * To whom correspondence should be addressed. B.L.C.: (504) 2801385 (phone); (504) 280-3185 (fax); bcushing@uno.edu (e-mail). C.J.O.: (504)280-6846(phone);(504)280-3185(fax);coconnor@uno.edu (e-mail). 3893 Chem. Rev. 2004, 104, 3893−3946

Facile Reduction of Tungsten Halides with Nonconventional, Mild Reductants. 2. Four Convenient, High-Yield Solid-State Syntheses of the Hexatungsten Dodecachloride Cluster W6Cl12 and Cluster Acid (H3O)2[W6(μ3-Cl)8Cl6](OH2)x, Including New Cation-Assisted Ternary Routes

Abstract: Tungsten hexachloride was reduced by Hg or Bi at moderately low temperatures (∼350 °C) to afford good yields (Hg, 73%; Bi, 85%) of W6Cl12 after conversion of the reduction product to the chloro acid (H3O)2[W6(μ3-Cl)8Cl6](OH2)x, recrystallization, and thermolysis in vacuo. Antimony was a less effective reductant because of the lower yield of chloro acid (31%) and the substantial quantities of insoluble byproducts found after HCl workup. The yield of (H3O)2[W6(μ3-Cl)8Cl6](OH2)x from WCl6 reduction by Sb improved dramatically to 79% with added KCl, while LiCl reduced the yield to only traces. In Bi reduction of WCl6, the yield of (H3O)2[W6(μ3-Cl)8Cl6](OH2)x decreased from 86 to 49% upon addition of NaCl, whereas added KCl had no effect on the yield. The Hg-, Bi-, Sb/KCl-, and Bi/KCl-based routes offer substantial experimental advantages over published methods for preparation of (H3O)2[W6(μ3-Cl)8Cl6](OH2)x and W6Cl12.

Facile Reduction of Tungsten Halides with Nonconventional, Mild Reductants. I. Tungsten Tetrachloride: Several Convenient Solid-State Syntheses, a Solution Synthesis of Highly Reactive (WCl4)x, and the Molecular Structure of Polymeric Tungsten Tetrachloride

Abstract: Polymeric (WCl4)x has been prepared in crystalline form from WCl6 by three new, safer solid-state approaches via mercury (in 83% yield), bismuth (82% yield), or antimony (97% yield) reduction. A modification of a published procedure for reduction of WCl6 with red phosphorus, which improves (WCl4)x purity, is also described. Highly reactive (WCl4)x powder can be prepared in 99% yield via tin reduction of WCl6 in 1,2-dichloroethane. (WCl4)x powder was readily converted in high yields to the known WCl4(MeCN)2 and W2Cl4(OMe)4(HOMe)2. The molecular structure of (WCl4)x, as determined by single-crystal X-ray diffractometry, consists of a polymer of opposite-edge-sharing bioctahedra with alternating short (W(1)−W(1A), 2.688(2) A) and long (W(1)···W(1B), 3.787(3) A) tungsten−tungsten distances. The acute W(1)−Cl(2)−W(1A) angle (69.4(2)°), obtuse Cl(1)−W(1)−W(1A) angle (94.99(12)°), short axial Cl(1)···Cl(1A) nonbonded distance (3.085(10) A, substantially less than twice the Cl van der Waals radius), and short W(1...

Magnetic nanoparticles: Synthesis, protection, functionalization, and application

Abstract: This review focuses on the synthesis, protection, functionalization, and application of magnetic nanoparticles, as well as the magnetic properties of nanostructured systems. Substantial progress in the size and shape control of magnetic nanoparticles has been made by developing methods such as co-precipitation, thermal decomposition and/or reduction, micelle synthesis, and hydrothermal synthesis. A major challenge still is protection against corrosion, and therefore suitable protection strategies will be emphasized, for example, surfactant/polymer coating, silica coating and carbon coating of magnetic nanoparticles or embedding them in a matrix/support. Properly protected magnetic nanoparticles can be used as building blocks for the fabrication of various functional systems, and their application in catalysis and biotechnology will be briefly reviewed. Finally, some future trends and perspectives in these research areas will be outlined.

Prospects of Colloidal Nanocrystals for Electronic and Optoelectronic Applications

Abstract: Nanocrystals (NCs) discussed in this Review are tiny crystals of metals, semiconductors, and magnetic material consisting of hundreds to a few thousand atoms each. Their size ranges from 2-3 to about 20 nm. What is special about this size regime that placed NCs among the hottest research topics of the last decades? The quantum mechanical coupling * To whom correspondence should be addressed. E-mail: dvtalapin@uchicago.edu. † The University of Chicago. ‡ Argonne National Lab. Chem. Rev. 2010, 110, 389–458 389

Colloidal nanocrystal synthesis and the organic–inorganic interface

Abstract: Colloidal nanocrystals are solution-grown, nanometre-sized, inorganic particles that are stabilized by a layer of surfactants attached to their surface. The inorganic cores possess useful properties that are controlled by their composition, size and shape, and the surfactant coating ensures that these structures are easy to fabricate and process further into more complex structures. This combination of features makes colloidal nanocrystals attractive and promising building blocks for advanced materials and devices. Chemists are achieving ever more exquisite control over the composition, size, shape, crystal structure and surface properties of nanocrystals, thus setting the stage for fully exploiting the potential of these remarkable materials.