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Two co-crystals of melatonin with piperazine and (1,4-diazabicyclo[2.2.2]octane), DABCO, and a hydrated ionic co-crystal with CaCl2 were obtained directly in the solid-state via kneading of the solid mixtures with a few drops of ethanol. The structure of the DABCO co-crystal, mel2·DABCO, was determined by single crystal X-ray diffraction, while those of the piperazine co-crystal, mel2·pip, isomorphous with the DABCO one, and the ionic co-crystal, mel2·CaCl2·2H2O, were determined from powder data. In the case of the ionic co-crystal with CaCl2, solubility measurements indicate that melatonin solubility in water increases by an order of magnitude with respect to the pure substance. [ABSTRACT FROM AUTHOR]

New binary and ternary solid solutions formed by p-chlorobenzyl alcohol (p-ClBA), p-bromobenzyl alcohol (p-BrBA) and their quasi-isostructural compound p-methylbenzyl alcohol (p-MeBA) have been prepared and characterized by DSC and powder X-ray diffraction. The binary and ternary solid solutions were synthesized by co-melting of p-MeBA/p-ClBA, p-MeBA/p-BrBA and p-ClBA/p-BrBA and by co-melting of p-MeBA/p-ClBA/p-BrBA in various molar ratios. By varying the relative concentrations, it has been possible to observe the consequent variations of the melting points of the solid solutions. For the binary 1 : 1 p-MeBA/p-BrBA and p-ClBA/p-BrBA compounds, single crystals were grown from solution and their structures were investigated by X-ray diffraction. [ABSTRACT FROM AUTHOR]

The title compound, [Fe(C10H15)2][Ni(C3OS4)2]·C4H8O or [Fe(Cp*)2][Ni(dmio)2]·THF, where [Fe(Cp*)2]+ is the deca­methyl­ferrocenium cation, dmio is the 2-oxo-1,3-dithiole-4,5-dithiol­ate dianion and THF is tetra­hydro­furan, crystallizes with two independent half-anion units [one Ni atom is at the centre of symmetry ( , , 0) and the other is at the centre of symmetry ( , 0, )], one cation unit (located in a general position) and one THF solvent mol­ecule in the asymmetric unit. The crystal structure consists of two-dimensional layers composed of parallel mixed chains, where pairs of cations alternate with single anions. These layers are separated by sheets of anions and THF mol­ecules. [ABSTRACT FROM AUTHOR]

The title compound, [Fe(C(10)H(15))(2)][Ni(C(3)OS(4))(2)].C(4)H(8)O or [Fe(Cp*)(2)][Ni(dmio)(2)] x THF, where [Fe(Cp*)(2)](+) is the decamethylferrocenium cation, dmio is the 2-oxo-1,3-dithiole-4,5-dithiolate dianion and THF is tetrahydrofuran, crystallizes with two independent half-anion units [one Ni atom is at the centre of symmetry ({1/2}, {1/2}, 0) and the other is at the centre of symmetry ({1/2},0, {1/2})], one cation unit (located in a general position) and one THF solvent molecule in the asymmetric unit. The crystal structure consists of two-dimensional layers composed of parallel mixed chains, where pairs of cations alternate with single anions. These layers are separated by sheets of anions and THF molecules.

In the title complex, trans-(2,2'-[cyclohexane-1,2-diylbis(nitrilomethylidyne)]diphenolato-kappa(4)O,N,N',O')nickel(II)-chloroform (1/1), [Ni(C(20)H(20)N(2)O(2))].CHCl(3), the Ni atom has a square-planar geometry, slightly tetrahedrally distorted. The Ni-N and Ni-O bonding distances are within the expected ranges for Ni-Schiff base derivatives. The diimine bridge has a gauche conformation with the cyclohexyl ring almost coplanar with the NiN(2)O(2) plane. The complex molecules pack in dimers with an Ni.Ni distance of 3.59 (1) A and form a three-dimensional structure displaying a herring-bone configuration. Channels are occupied by solvent molecules, which are involved in C-H.O hydrogen bonds with the ligand O atoms.

The gold complexes n-Bu4N[Au(alpha-tpdt)2] (5), n-Bu4N[Au(dtpdt)2] (4) and n-Bu4N[Au(tpdt)2] (6) based on new dithiothiophene ligands (alpha-tpdt= 2,3-thiophenedithiolate, dtpdt=2,3-dihydro-5,6-thiophenedithiolate and tpdt = 3,4-thiophenedithiolate) have been prepared and characterised. These gold(III) complexes are diamagnetic, but they can be oxidised with iodine to the paramagnetic compounds [Au(alpha-tpdt)2] (8), [Au(dtpdt)2] (7) and n-Bu4N[[Au(tpdt)2]n-2] (9), which were isolated as fine powders and which exhibit paramagnetic susceptibilities that are almost temperature independent with room temperature values of 2.5 x 10(-4), 2.0 x 10(-4) and 5 x 10(-4) emu x mol(-1), respectively. Interestingly, the neutral complex [Au(alpha-tpdt)2] (8) as a polycrystalline sample displays the properties of a metallic system with a room temperature electrical conductivity of 6 S x cm(-1) and a thermoelectric power of 5.5 microVK(-1); this is the first time that this metallic property has been observed in a molecular system based on a neutral species.

The title compound, K(4)Na(2)[V(10)O(28)].10H(2)O, is isostructural with the known disodium tetraammonium salt of the centrosymmetric [V(10)O(18)](6-) anion.