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Acta Cryst. (2014). A70, C1006
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Liquid-liquid solvent extraction has become the primary research topic for separating mixtures of rare-earths. [1] Current research on this topic focuses on extraction processes involving ionic liquids as basic extracting agents. In the aqueous phase, the rare-earth is coordinated by the anionic entities of the ionic liquid, forming an anionic complex. The large organic cation of the ionic liquid neutralizes the complex (ion-pair complex) and migrates the entity to an organic phase. The choice of these agents is solely based on the calculation of thermodynamical extraction parameters, whilst structural information about these compounds is rare or even non-existent. Our research focuses on obtaining structural information via crystallography on the above-mentioned molecules and relating the interactions between anion and cation to the stability of the complexes. A difference in stability between the anionic complex and cation can give a different extractability. Different rare-earth chloride salts were dissolved in an aqueous phase, containing ionic liquids with β-diketonate anions and 1-alkyl-3-methylimidazolium cations. After the extraction, crystals of the formed compounds are grown from the organic phase and measured. Current results show us that an intermolecular non-classical C-H ... O hydrogen bond is persistent across the different molecules, whilst small interactions between the cation side chain and halogens on the β-diketonate add extra stability to the crystal structure. Structures formed with 2-thenolytrifluoroactylacetonate anions have no intention to form side chain interactions, leaving the alkyl chain of the 1-alkyl-3-methylimidazolium in a void, whilst structures formed with hexafluoroacetylactonate have strong side chain interactions, which leads to a better packing. The different solubility of both compounds can be related to the different interactions and stability in the crystal structure.

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Acta Cryst. (2014). A70, C1044
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Since many years regional and national crystal growing competitions are successfully organized for pupils in countries such as Australia, Belgium, Canada, England, France and Singapore, and for sure in many schools on a more local basis. For most competitions pupils have to grow single crystals in the class room during a limited period of time (e.g. four weeks) of a limited amount of starting material provided by the organizers. Submitted single crystals are then judged by a jury based on the weight and the quality of the crystal. Typical compounds used as starting materials for such competitions are alum (aluminium potassium sulphate dodecahydrate), copper (II) sulphate pentahydrate, borax (sodium tetraborate decahydrate), ammonium iron (II) sulphate hexahydrate, potassium dihydrogen phosphate and ammonium magnesium sulphate hexahydrate. To celebrate the International Year of Crystallography a small IUCr working group of coordinators of current crystal growing competitions took the initiative to stimulate as many countries as possible to organize a regional or national crystal growing competition. To facilitate this, the IUCr offers all possible support for newcomers in the form of a time line, protocols and suggestions for judging and prize awarding. This information is available on the IYCr website www.iycr2014.org/participate/crystal-growing-competition, together with a brand new animated video 'How to grow a single crystal - with Johanna' illustrating the protocol. With the celebrations of the International Year of Crystallography in mind the lead partners IUCr and UNESCO organize also a world-wide crystal growing competition. The aim of this competition is that participants grow their own crystals (whether involved in a regional/national competition or not) and convey their experience through a short video or essay. A panel of judges will evaluate the entries using criteria such as creativity, esthetic value, description of working plan and experimental work, clarity of explanations and scientific background. For countries were no crystallographers can take the lead to initiate a competition in 2014 the network of UNESCO schools will be used, an initiative which will start in September 2014.

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Acta Cryst. (2014). A70, C1245
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A series of new platinum(II) complexes containing chelating safrole (or its derivatives) and various amines have been synthesized to evaluate their anticancer activity. Here we report the structure determination of [Pt((MeO)2Ph)(o-toluidine)Cl] (1) and [Pt((MeO)2Ph)(piperidine)Cl] (2), with (MeO)2Ph 3,4-dimethoxyphenyl-2-propene. Plate-like crystals of (1), suitable for x-ray diffraction measurement were obtained by slow evaporation from an ethanol solution. Rod-like crystals of (2) were harvested from ethanol after slow evaporation of acetone from an ethanol-acetone solution. Diffraction data were collected on a diffractometer equipped with a Bruker-AXS SMART 6000 CCD detector and integrated by the program SAINT. A multi-scan absorption correction was performed by the program SADABS. Both structures were solved by direct methods using the SHELXS program and refined according to the least-squares method to R-values of for 0.0204 (1) and 0.0280 for (2). The crystal of (1) to the orthorhombic space group P212121 and that of (2) belongs to the triclinic space group P-1. The asymmetric unit of (1) comprises one molecule of [Pt((MeO)2Ph)(o-toluidine)Cl]. The asymmetric unit of (2) consists of one ethanol molecule and one [Pt((MeO)2Ph)(piperidine)Cl] molecule. Both structures are similar with respect to the configuration and geometry of the Pt complex. Considering the centroid Cg of the allyl C=C bond as one ligand, the coordination geometry of Pt is square planar (other ligands are Cl, N (amine) and C (phenyl ring)). The angle between the best planes through the (MeO)2Ph and amine ligands is 84.3(1)0 in (1) and 25.2(5)0 in (2). The best plane through the allyl group makes an angle of 55.6(2)0 and 56.4(4)0 with the best plane through the (MeO)2Ph group, respectively in (1) and (2). The allyl double bond C=C is nearly perpendicular to Pt-Cg line, 89.8(2)0 in (1) and 87.4(8)0 in (2). For (1) the packing is essentially the result of van der Waals' interactions and two weak hydrogen bonds of type C-H...Cl and C-H...O. In (2) the packing is determined by the O-H...O hydrogen bond (O...O distance 2.870(4) Å) between ethanol and one of the methoxy substituents.
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