Milan Melnik

Abstract: The bonding properties of thiocyanate groups of over one hundred copper species, studied by X-ray analysis were analysed. It is shown that the bonding properties of thiocyanate groups in heterogeneous copper thiocyanate complexes depend on the size of the positive charge on the copper atom.

Abstract: This review summarizes the data for over nine hundred dimeric Cu(II) coordination compounds. There are several types of the bridges, from which doubly bridges by far prevail. The most common ligands are O− and N− donors. From the stereochemical point of view, a square-pyramidal arrangement with different degrees of distortion about Cu(II), is the most common. Several relationships were found between the Cu-Cu distances and the Cu-L-Cu bridge angle and the type of bridging, between the intra-ligand L-Cu-L ring angles and coordination numbers.

Abstract: Nanocrystals are fundamental to modern science and technology. Mastery over the shape of a nanocrystal enables control of its properties and enhancement of its usefulness for a given application. Our aim is to present a comprehensive review of current research activities that center on the shape-controlled synthesis of metal nanocrystals. We begin with a brief introduction to nucleation and growth within the context of metal nanocrystal synthesis, followed by a discussion of the possible shapes that a metal nanocrystal might take under different conditions. We then focus on a variety of experimental parameters that have been explored to manipulate the nucleation and growth of metal nanocrystals in solution-phase syntheses in an effort to generate specific shapes. We then elaborate on these approaches by selecting examples in which there is already reasonable understanding for the observed shape control or at least the protocols have proven to be reproducible and controllable. Finally, we highlight a number of applications that have been enabled and/or enhanced by the shape-controlled synthesis of metal nanocrystals. We conclude this article with personal perspectives on the directions toward which future research in this field might take.

Abstract: This article describes the state of the art in the field of antimicrobial polymeric systems during the last decade. Keeping in mind the multitude of existing systems, a classification of the different materials is carried out dividing basically those synthetic polymers that: (a) exhibit antimicrobial activity by themselves; (b) those whose biocidal activity is conferred through their chemical modification; (c) those that incorporate antimicrobial organic compounds with either low or high molecular weight; and (d) those that involve the addition of active inorganic systems. This classification is not absolutely unique and in occasions some described polymeric systems could belong to more than one section. However, the purpose of this review is to provide a handy overall vision of the antimicrobial synthetic polymers world.

Abstract: The use of planar or tridimensional cyclic and acyclic Schiff bases, their polyamine homologues and related derivatives, for the formation of mononuclear and especially polynuclear complexes, is reported. Attention is devoted to the synthetic pathways and to the structural aspects of the resulting systems, particularly the role of the shape of the coordinating ligands and of the different metal ions in directing the synthesis totally or preferentially towards mono-, di- or poly-nuclear entities. Special care is paid to compartmental ligands, owing to their ability to bind two or more metal ions in close proximity. The insertion of asymmetry into these ligands provides important diversification of the coordinating sites and allows for different and well defined recognition processes involving specific ions and/or molecules at the adjacent coordinating sites. New molecular materials, devices and probes for specific recognition and detection in the solid state or solution take advantage of the presence of different metal ions at appropriate distances from each other in a preordered stereochemical environment with variation of oxidation state, magnetic, optical and redox properties. Such polynuclear systems can exhibit unusual reactivity or catalysis.