The solid solutions Cu2Fe1-X CoX SnS4, with stannite-type structure are stable up to about 800°C. The electrical properties of the Cu2Fe0.4Co0.6SnS4 ceramic were investigated by complex impedance. The real and imaginary dielectric permittivity dependence with the temperature were measured between 10kHz and 1 MHz in temperature range 77-280K, finding that the ceramic present the characteristics behavior of a dielectric relaxation between 100 and 250 K, with a maximum at approximately 200 K. The electric permittivity found has orders of magnitude between 10² and 10³. A space charge polarization mechanism is suggested to explain the observed electric relaxation.

12b-Hydroxy-5,6,8,12b-tetrahydroisoindolo[1,2-α] isoquinolin-8-one (4), 5,6,8,12b-tetrahydroisoindolo[1,2-α]isoquinoline (5) and 12b-hydroxy-5,6,8,12b-tetrahydroisoindolo[1,2-α]isoquinoline (6) were obtained by reduction of 4,5,8,12b-tetrahydroisoindolo[1,2-α]isoquinolin-8-one (3) with LiAlH4/THF/N2. The precursor and products were characterized by NMR spectroscopy and the X-ray crystal structure of 5 hydrochloride monohydrate (5a) was determined. ¹H and 13C NMR spectra were completely assigned for compounds 3, 4, and 5a, using two-dimensional experiments (H-H COSY, HMQC, HMBC and H-H NOESY).

The title compound (1, trivial name: 9 (or 3)-nitrocytisine) crystallizes with two independent molecules in the asymmetric unit. In its structure two rings form a bispidine framework that is fused to a 3-nitro-2-pyridone group. The half-normal probability plot reveals that the two molecules do not show any significant geometrical differences, except in conformations of the nitro-group, which is involved in intermolecular interactions. The crystal packing structure of the title compound is described in terms of three-dimensional supramolecular arrays built up from chains of N-H-O (nitro-group), hydrogen bonds and weak intermolecular C- H … O=C interactions, with graph-set descriptors C²2(6) and C²2(JQ) motifs, which together result in R(4)4(26) rings motifs. These chains are additionally stabilized by intermolecular NO2…π interactions.

The crystal structure of ethyl 7-hydroxy-2-oxo-2H-chromene-3-carboxylate monohydrate (1), C12H10O5.H2O, was established by X-ray crystallographic analysis. The molecule of the title compound is essentially planar except for the carboxylate substituent group. The crystal packing supramolecular array arises from hydrogen bonds and intermolecular C-H - O=C contacts of the organic molecules and solvent water molecules, with graph-set descriptor R²4 (8), R²1 (6), R(4)4 ( 20) and C (5) motifs. The water molecules are involved as donors and acceptors. The hydrogen bond and intermolecular interaction network is reinforced by stacking of the sheet through p-p interactions.

The title compound was prepared by cyclization of 2-(3,4-methylenedioxyphenyl)ethyl-3-hydroxyisoindolin-l-one in concentrated hydrochloric acid. The compound crystallizes in the orthorhombic space group Pca2(1) (No. 29) with a = 27.034(5) Å, b = 4.5093(9) Å, c = 10.667(2)Å, V = 1300.4(4) ų and Z = 4. The crystal consists of a single enantiomer. The molecule consists of two essentially flat moieties forming an dihedral angle of 116.3(2)°. The crystal slructure has intermolecular C-H-O interactions resulting in chains that run along the crystallographic c-axis.

O tiofosfato quaternário de metal alcalino e terra rara K4Sm2[PS4]2[P2S6] foi sintetizado pelo método cerâmico e caracterizado por difratometria de raios X de pó (XRD), microscopia eletrônica de varredura com microanálise de raios X (SEM-EDX), medidas de impedância eletroquímica e medidas magnéticas. A estrutura cristalina consiste de camadas de ²∞Sm2[PS4]2[P2S6]4- separadas por cátions K+. As medidas de condutividade elétrica indicam que o composto é um semicondutor com uma resistividade de 1,0 x 10(11) Ω cm. O momento magnético, obtido a partir de χ-1 versus T a baixa temperatura, é igual a 0,57 μB.

The quaternary alkali metal, rare earth thiophosphate phase K4Sm2[PS4]2[P2S6] was synthesized by ceramic method and characterized by powder X-ray diffraction (XRD), SEM-EDX scanning electron microscope-microprobe analyses, electrochemical impedance and magnetic measurements. The crystal structure consists of layers of ²∞Sm2[PS4]2[P2S6]4- separated by K+ cations. The electrical conductivity measurements indicate that the compound is a semiconductor with a resistivity of 1.0 x10(11) Ω cm. The magnetic moment, evaluated from χ-1 versus T at low temperature is 0.57 µB.

The intercalation compounds Li0,43(PEO)2.4(H2O)1.4K0.57BiP2S6 and Li0.38(PEO)2.1(H2O)1.6K0.62SbP2S6 have been synthesized by the insertion of polyethylene oxide PEO in LiKMP2S6 (M=Bi, Sb), that contained Li+ and K+ exchangeable cations in their interlayer space. The polymer PEO is able to associate interlayer Li+ cation modifying the ionic conductivity of pristine phases. These intercalation compounds constitute a new family of intercalates in the thiophosphate of Bi and Sb with Polyethylene oxide as guest species. They have been characterized by powder X-ray diffraction, FTIR-Raman, DTA/TGA analysis and electrical conductivity measurements. The studied nanocomposite shows values of electrical conductivity (σi) of about 10-6 Ω-1 cm-1 at room temperature.