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This paper discusses the development of environmentally-friendly precursor inks suited for ink-jet printing of functional ceramic coatings. We synthesized superconducting materials, SrTiO3 thin films for coated conductor applications and transparent TiO2 photocatalytic coatings. Here, we discuss all aspects of ink formulation, including the stabilization of metal ions, nanoparticle inks or combination of both. This demands the investigation and determination of the inks rheological parameters. Ceramic nanoparticles are often incorporated in our inks to decrease thermal processing temperatures (e.g., TiO2 or YSZ coatings...) or enhance the properties of the functional ceramic coating (e.g., pinning centres in superconducting coatings). These ceramic nanoparticles (ZrO2, HfO2, TiO2...) are synthesized through methods based on microwave heating from aqueous and/or organic solutions. With that, we aim at developing smart and environmentally friendly processes that require lower energy input. [ABSTRACT FROM AUTHOR]

The hydration reaction is defined as the transfer of an ion or neutral chemical species from the gaseous phase into water, Mn+(g) → Mn+(aq). In this process, water molecules bind to metal ions through ion-dipole bonds of mainly electrostatic character. The hydration reaction is always strongly exothermic with increa sing heat of hydration with increasing charge density of the ion. The structures of the hydrated metal ions in aqueous solution display a variety of configurations depending on the size and electronic properties of the metal ion. The basic configurations of hydrated metal ions in aqueous solution are tetrahedral, octahedral, square antiprismatic, and tricapped trigonal prismatic. This paper gives an overview of the structures of hydrated metal ions in aqueous solution with special emphasis on those with a non-regular coordination figure. Metal ions without d-electrons in the valance shell form regular aqua complexes with a coordination figure, allowing a maximum number of water molecules to be clustered around the metal ion. This number is dependent on the ratio of the metal ion radius to the atomic radius of oxygen in a coordinated water molecule (1.34 Å). The lighter lanthanoid(III) ions have a regular tricapped trigonal prismatic configuration with the M-O distance to the capping water molecules somewhat longer than to the prismatic ones. However, with increasing atomic number of the lanthanoid( III) ions, an increasing distortion of the capping water molecules is observed, resulting in a partial loss of water molecules in the capping positions for the heaviest lanthanoids. Metal ions with d4 and d9 valance shell electron configuration, as chromium(II) and copper( II), respectively, have Jahn—Teller distorted aqua complexes. Metal ions with low charge and ability to form strong covalent bonds, as silver(I), mercury(II), palladium(II), and platinum( II), often display distorted coordination figures due to the second-order Jahn—Teller effect. Metal ions with d10s² valence shell electron configuration may have a stereochemically active lone electron pair (hemi-directed complexes) or an inactive one (holo-directed). The hydrated tin(II), lead(II), and thallium(I) ions are hemi-directed in aqueous solution, while the hydrated bismuth(III) ion is holo-directed. The structures of the hydrated cationic oxometal ions are reported as well. [ABSTRACT FROM AUTHOR]

The synthesis of beryllium halide etherates and the solution behavior in benzene, dichloromethane, and chloroform was studied by NMR, IR, and Raman spectroscopy. Mononuclear units of [BeX2(L)2] (X = Cl, Br, I; L = Et2O, thf) were identified as the favorably formed species in solution. Treatment of the mononuclear diethyl ether beryllium halide adduct with one equivalent beryllium halide formed the dinuclear compounds [BeX2(OEt2)]2 (X = Cl, Br, I). The solid-state structures of [BeCl2(thf)2] and [BeBr2(thf)2] have been determined by single crystal X-ray diffraction analysis. [BeI2(thf)2] decomposed in all solvents. In CD2Cl2 the salt [Be(thf)4]I2 was formed, whereas in C6D6 and CDCl3, BeI2 precipitated and [BeI(thf)3]+, [Be(thf)4]2+ together with the thf ring-opening product [Be(μ2-O(CH2)4I)I(thf)]2 were observed in solution. [ABSTRACT FROM AUTHOR]

The synthesis of bis(diphenylphosphino)ethane (dppe) and PMe3 mono-adducts [(dppe)BeCl2]n and [(PMe3)BeCl2]2 is described and their spectroscopic properties discussed. Hydrolysis of these two compounds and of the bis(diphenylphosphino)propane (dppp) adduct to BeCl2 gave [dppeH2][BeCl4], [Me3PH]n[Be4Cl9]n and [dpppH2][Be2Cl6], which have been isolated and structurally characterized by single crystal X-ray diffraction. The reactions of [(PMe3)BeCl2]2 with p-cresole gave [Me3PH]2[Be2Cl4(OC7H7)2]. This phenoxide together with [(Me3PO)2Be2Cl4], the oxidation product of [(PMe3)BeCl2]2, have also been structurally characterized. [ABSTRACT FROM AUTHOR]

The diphenylphosphinites [(THF)Li(OPPh2)]4 and [(THF)2Be(OPPh2)2] have been synthesized via direct deprotonation of diphenylphosphine oxide with nBuLi and BePh2, respectively, as well as via salt metathesis. These compounds were characterized by multinuclear NMR spectroscopy, and the side-products of the reactions obtained under various reaction conditions have been identified. The beryllium derivative could not be isolated and decomposed into diphosphine oxide Ph2PP(O)Ph2. The solid-state structure of this final product together with that of [(THF)Li(OPPh2)]4 have been determined by single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

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Rational design of title ligands and their transition metal complexes gave the high effective catalysts for hydrogen economy and perspective "stimuli-responsive" luminescent materials. Together with the above novel cyclic aminomehtylphospine ligands have showed a row of unpredicted properties like spontaneous formation of macrocyclic molecules, unique reversible slitting of macrocycles on to the smaller cycles, rapid interconversion of the isomers catalyzed by both acids and transitional metals, bridging behavior of usually chelating ligands and unexpected high influence of handling substituents on N-atoms on to the catalytic and luminescent properties of P-complexes. [ABSTRACT FROM AUTHOR]

Over the course of time, several effects which are associated with the phenomenon of an optically-induced spin transition were found. With this contribution, we would like to give the reader a brief overview of several photonically-induced SCO effects by outlining their relationship to one another. [ABSTRACT FROM AUTHOR]

Alfred Werner was awarded the Nobel Prize in Chemistry just over 100 years ago. We recall briefly the era in which he was working, his co-workers, and the equipment he used in his laboratories. His ideas were ground breaking: not only does a metal ion have a primary valency ('hauptvalenz', now the oxidation state), but also a secondary valency, the coordination number ('nebenvalenz'). At that time some refused to accept this idea, but he realised that his new thinking would open up new areas of research. Indeed it did. We illustrate this for the emerging field of medicinal metal coordination chemistry, the design of metal-based therapeutic and diagnostic agents. The biological activity of metal complexes depends intimately not only on the metal and its oxidation state, but also on the type and number of coordinated ligands, and the coordination geometry. This provides a rich platform in pharmacological space for structural and electronic diversity. It is necessary to control both the thermodynamics (strengths of metal-ligand bonds) and kinetics of ligand substitution reactions to provide complexes with defined mechanisms of action. Outer-sphere interactions can also play a major role in target recognition. Our current interest is focussed especially on relatively inert metal complexes which were very familiar to Werner (RuII, OsII, RhIII, IrIII, PtII, PtIV). [ABSTRACT FROM AUTHOR]

A review of recent developments in silver(I)-catalyzed nitrene insertions into olefin and C-H bonds is presented, with a particular emphasis on reactions where the chemoselectivity can be tuned to promote either aziridination or C-H amination. The scope and synthetic utility of various silver catalysts are described, as well as preliminary investigations into the mechanisms of silver-catalyzed aminations. [ABSTRACT FROM AUTHOR]

As a consequence of the ongoing development of enhanced computational resources, theoretical chemistry has become an increasingly valuable field for the investigation of a variety of chemical systems. Simulations employing a hybrid quantum mechanical/molecular mechanical (QM/MM) molecular dynamics (MD) technique have been shown to be a particularly promising approach, whenever ultrafast (i.e., picosecond) dynamical properties are to be studied, which are in many cases difficult to access via experimental techniques. Details of the quantum mechanical charge field (QMCF) ansatz, an advanced QM/MM protocol, are discussed and simulation results for various systems ranging from simple ionic hydrates to solvated organic molecules and coordination complexes in solution are presented. A particularly challenging application is the description of proton-transfer reactions in chemical simulations, which is a prerequisite to study acidified and basic systems. The methodical requirements for a combination of the QMCF methodology with a dissociative potential model for the description of the solvent are discussed. Furthermore, the possible extension of QM/MM approaches to solid/liquid interfaces is outlined. [ABSTRACT FROM AUTHOR]

A set of terms, definitions, and recommendations is provided for use in the classification of coordination polymers, networks, and metal--organic frameworks (MOFs). A hierarchical terminology is recommended in which the most general term is coordination polymer. Coordination networks are a subset of coordination polymers and MOFs a further subset of coordination networks. One of the criteria an MOF needs to fulfill is that it contains potential voids, but no physical measurements of porosity or other properties are demanded per se. The use of topology and topology descriptors to enhance the description of crystal structures of MOFs and 3D-coordination polymers is furthermore strongly recommended. [ABSTRACT FROM AUTHOR]

Multimetal complexes provide a variety of interesting structures, unique properties, and functions. Such sophisticated functions are often produced by synergistic and cooperative interactions among the metal ions accumulated in the restricted small area of the multimetal systems. We describe novel three strategies (i.e., macrocyclic, C-shape, and multimetal template) for the preparation of the multimetal supramolecular systems by the cooperative metal binding of a multi-Schiff-base and multi-oxime ligands, and their characteristic structures and functions. The three approaches are versatile and effective because the employed coordination reactions smoothly and quickly proceeded under mild conditions to quantitatively form the desired coordination structures. The multimetal supramolecular systems obtained here exhibit the synergistic and cooperative functions for ion recognition, magnetic properties, helicity control, and modulation of reaction selectivity. These types of multimetal complexes could be developed for a cascade functional supramolecular system that shows highly synergistic properties, integrated multifunctions, and function amplification. [ABSTRACT FROM AUTHOR]

The products obtained by forcing the reaction with nucleosides (guanosine, Guo, and adenosine, Ado) of potential anticancer drugs for nongenomic targets [PtCl(O,O'-acac)(L)] (L = dimethyl sulfoxide, DMSO; dimethyl sulfide, DMS), closely related to their very powerful organometallic analogues [Pt(O,O'-acac)(γ-acac)(L)], have been studied. [PtCl(O,O'-acac)(L)] and [Pt(O,O'-acac)(γ-acac)(L)] complexes were reported unreactive toward nucleobases. Aquo species [Pt(O,O'-acac)H2O(L)]+, obtained from [PtCl(O,O'-acac)(L)] by Ag+ driven coordinated Cl– removal, gave access to [Pt(O,O'-acac)(L)(nucleoside)]+ ([Pt(O,O'-acac)(DMSO)(Guo)]+, [Pt(O,O'-acac)(DMS)(Guo)]+, [Pt(O,O'-acac)(DMSO)(Ado)]+). The effect of the chelate oxygen donor acac (with respect to a chelate diammine), the role of the sulfur ligand (DMSO, DMS), and the influence of the purinic nucleoside itself on the coordinated Guo or Ado dynamic motions in [Pt(O,O'-acac)(L)(nucleoside)]+ complexes have been investigated by NMR spectroscopy. Interestingly, a slow rotation of nucleobase around the Pt–N(7) bond with formation of two rotamers was observed already at room temperature only in the case of [Pt(O,O'-acac)(DMSO)(Guo)]+. On the other hand, no hindered rotation at room temperature was detected in the analogous [Pt(O,O'-acac)(DMS)(Guo)]+ and [Pt(O,O'-acac)(DMSO)(Ado)]+ complexes. Data suggest that rotation of the nucleoside in [Pt(O,O'-acac)(L)(nucleoside)]+ is very different with respect to the analogous [Pt(diammine)(L)(nucleoside)]2+ systems, due to specific interactions between the acac chelate ligand, the DMSO, and the nucleobase. [ABSTRACT FROM AUTHOR]