Crystal structure of nitrate tris(4-allylthiosemicarbazide)-chromium(III) hydrate

The crystal structure of nitrate tris(4-allylthiosemicarbazide)chromium(III) hydrate [CrL₃](NO₃)₃(H₂O)_1.05 (I), where L is 4-allylthiosemicarbazide, is determined. The asymmetric unit of the cell of the crystal structure of I contains a complex of a chromium ion with three bidentate coordinated molecules L. The outer coordination sphere of the central atom contains a disordered water molecule and three nitrate ions. The coordination polyhedron of the chromium atom in complex I is an octahedron. In the crystal, the complexes of the compound under study are joined with each other by the outer-sphere nitrato groups into a three-dimensional branched net of hydrogen bonds.     

Crystal structure of diiminoxylpinacone hydrate

The structure of 4,4-bis(4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl) is solved by x-ray methods. The compound forms a strong crystalline monohydrate.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1529–1531, July, 1991.     

Crystal structure of magnesium(II) diaquatetracarbamidenitrate

Magnesium(II) diaquatetracarbamidenitrate nitrate was structurally studied. Crystals of composition [Mg(H₂O)₂(ur)₄](NO₃)₂ (I) are monoclinic, Z = 2, P2₁/n, a = 6.449(1) Å, b = 17.670(2) Å, c = 7.578(1) Å; β = 91.637(2)°. In the structure of complex I, the central magnesium atom has octahedral geometry: the four carbamide molecules are in equatorial positions, and water molecules occupy axial positions.     

Crystal structure of hexadimethylsulfoxidenickel(II) tetraisothiocyanatozincate

A new complex, hexadimethylsulfoxidenickel(II) tetraisothiocyanatozincate [Ni(DMSO)₆][Zn(NCS)₄](I), is synthesized. Its crystal structure is determined by X-ray diffraction analysis. Compound I forms light green, monoclinic crystals shaped like plates: a = 8.4358(8) Å ,b = 21.655(2) Å, c = 10.8351(8) Å = 105.162(7)°, V = 1910.4(3) ų, space group P2₁/m, Z = 2, (calcd) = 1.434 g/cm ³ , µ= 1.699mm ^–1. The Zn atom has a tetrahedral environment, while the Ni atom has an octahedral environment.Translated from Koordinatsionnaya Khimiya, Vol. 30, No. 12, 2004, pp. 939–942.Original Russian Text Copyright © 2004 by Cherkasova, Tsalko.     

Crystal structure of lead(II) dipivaloylmethanate

The volatile complex of lead(II) with 2,2,6,6-tetramethylheptane-3,5-dione is investigated by X-ray diffractometry. Crystal data: a = 10.901(2), b = 21489(4), c = 10.203(2) å, space group Pccn (N 56), V = 2503.4(8) å³, M = 573.74, Z = 4, d_calc = 2.522 g/cm³. The crystal structure is of molecular type; the molecule of the complex has a nonplanar structure. The lead atom is coordinated by four oxygen atoms of the two bidentate ligands. Films of the complex on substrates of Si and SiO₂ single crystals, melted quartz, and glass were obtained by thermal evaporation in vacuum. X-Ray diffraction analysis of the polycrystals and films of the complex showed that the films are distinctly textured along the b axis.     

Crystal structure of copper(II) bis-hexafluoroacetylacetonate

An X-ray diffraction investigation has performed for copper(II) bis-hexafluoroacetylacetonate (Bruker AXS P4 automatic diffractometer, MoK radiation, t = –25°C). Crystal data for C₁₀H₂CuF₁₂O₄: a = 5.530(1) Å, b = 6.038(1) Å, c = 11.266(2) Å, = 95.948(3)°, = 101.743(3)°, = 92.298(3)°, space group; P1, V = 365.6(1) ų, Z = 1, d _calc = 2.169 g/cm³. The square-planar environment of the copper atom (Cu-O_av 1.912 Å, O-Cu-O_av 93°) is completed to bipyramidal by two fluorine atoms of the neighboring molecules, Cu...F 2.71 Å and 2.75 Å.Original Russian Text Copyright © 2004 by S. A. Gromilov, I. A. Baidina, P. A. Stabnikov, and G. V. RomanenkoTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 502–507, May–June 2004.     

Crystal structure of diammine(malonato)palladium(II)

Diammine(malonato)palladium(II) is synthesized by the reaction of [Pd(NH₃)₄](NO₃)₂ with malonic acid, and its crystal structure is determined by single crystal X-ray diffraction. Distorted coordination square of the Pd(II) atom is formed by two N atoms of two ammonia molecules and two O atoms of bidentate malonate ligand. The average Pd-N and Pd-O distances are 2.018(7) ? and 2.014(2) ?, respectively. The molecules are stacked in such a way that the planes of coordination squares are parallel with the Pd...Pd distances between the nearest neighbors in a stack of 4.039 ?.     

Crystal structure and fluorescence/phosphorescence of two novel Cd(II) coordination polymers

Two novel Cd(II) coordination polymers [Cd₄(C₆H₄O₂N)₈(H₂O)₄]_n (1) and [Cd₂(C₁₀H₂O₈)(H₂O)₆]_n (2) have been synthesized under hydrothermal condition and structurally characterized. Crystal data: (1), orthorhombic, Pbca, a=11.4494(19) Å, b=12.0969(6) Å, c=17.4073(8) Å, V=2410.9(4) ų, Z=8, D _calc=2.064 g·cm⁻³; (2), triclinic, P , a=5.5962(7) Å, b=7.7758(6) Å, c=9.6975(10) Å, α=111.981(5)°, β=101.649(6)°, γ=98.240(5)°, V=371.95(7) ų, Z=2, D _calc=2.603 g·cm⁻³. Complex (1) possesses three-dimensional infinite structure, while complex (2) adopts two-dimensional layers and the layers are connected by the many types of hydrogen bonds, forming three-dimensional network. Study results of the photophysical properties show that both complexes can emit strong blue fluorescence and complex (1) also emits phosphorescence (λ ^pl _max=511 nm, τ=32 ms) in the solid state at room temperature.     

Crystal structure and magnetic properties of two isomeric three-dimensional pyromellitate-containing cobalt(II) complexes

The hydrothermal preparation, crystal structure determination, and magnetic study of two isomers made up of 1,2,4,5-benzenetetracarboxylate and high-spin Co(II) ions of formula [Co2(bta)(H2O)4]n x 2n H2O (1 and 2; H4bta = 1,2,4,5-benzenetetracarboxylic acid) are reported. 1 and 2 are three-dimensional compounds whose structures can be described as (4,4) rectangular layers of trans-diaquacobalt(II) units with the bta(4-) anion acting as tetrakis-monodentate ligand through the four carboxylate groups, which are further connected through other trans-[Co(H2O)2](2+) (1) and planar [Co(H2O)4](2+) (2) entities, with the bridging units being a carboxylate group in either the anti-syn (1) or syn-syn (2) conformations and a water molecule (2). The study of the magnetic properties of 1 and 2 in the temperature range 1.9-300 K shows the occurrence of weak antiferromagnetic interactions between the high-spin Co(II) ions, with the strong decrease of chi(M)T upon cooling being mainly due to the depopulation of the higher energy Kramers doublets of the six-coordinated Co(II) ions. The computed values of the exchange coupling between the Co(II) ions across anti-syn carboxylate (1) and syn-syn carboxylate/water (2) bridges are J = -0.060 (1) and -1.90 (2) cm(-1) (with the Hamiltonian being defined as H = -Jsigma(i,j)S(i) x S(j)). These values follow the different conformations of the carboxylate bridge in 1 (anti-syn) and 2 (syn-syn) with the occurrence of a double bridge in 2 (water/carboxylate).