Structure and some properties of [UO<Subscript>2</Subscript>(C<Subscript>5</Subscript>H<Subscript>12</Subscript>N<Subscript>2</Subscript>O)<Subscript>5</Subscript>](ClO<Subscript>4</Subscript>)<Subscript>2</Subscript>

Compound [UO₂(C₅H₁₂N₂O)₅](ClO₄)₂ is synthesized and characterized by thermogravimetry, IR spectroscopy, and X-ray diffraction. The compound crystallizes in the monoclinic crystal system; a = 15.2985(9) Å, b = 26.9676(15) Å, c = 20.6962(11) Å, β = 100.697(1)°, space group P2₁/c, Z = 8, and R = 0.0445. Discrete [UO₂(C₅H₁₂N₂O)₅]²⁺ groups belonging to the AM ₅ ¹ crystal chemical group of uranyl complexes (A = UO ₂ ²⁺ and M ¹=C₅H₁₂N₂O) are uranium-containing structural units of the crystals.     

Synthesis and crystal structure of the [Co<Subscript>2</Subscript>(Nicotinamide)<Subscript>4</Subscript>(C<Subscript>4</Subscript>H<Subscript>9</Subscript>COO)<Subscript>4</Subscript>(H<Subscript>2</Subscript>O)] complex

The [Co₂ L ₄(C₄H₉COO)₄(H₂O)] coordination compound of cobalt(II) valerate with nicotinamide (L) is synthesized and studied by IR spectroscopy. The crystal structure of the synthesized compound is determined. The crystals are triclinic, and the unit cell parameters are as follows: a = 10.2759(10) Å, b = 16.3858(10) Å, c = 16.4262(10) Å, α = 100.538(10)°, β = 101.199(10)°, γ = 90.813 (10)°, Z = 2, and space group P \(\bar 1\). The structural units of the crystal are dimeric molecular complexes in which pairs of cobalt atoms are linked by triple bridges formed by oxygen atoms of two bidentately coordinated valerate anions and a water molecule. The octahedral coordination of each cobalt atom is complemented by the pyridine nitrogen atoms of two nicotinamide ligands and the oxygen atom of the monodentate valerate group. The hydrocarbon chains of the valerate anions are disordered over two or three positions each.     

Crystal structure of the new radical cation salt (<Emphasis Type="Italic">DOET</Emphasis>)<Subscript>4</Subscript>[Fe(CN)<Subscript>5</Subscript>NO]<Subscript>1.25</Subscript>(C<Subscript>6</Subscript>H<Subscript>5</Subscript>Cl)<Subscript>0.75</Subscript>

A new radical cation salt based on 4,5-(1,4-dioxanediyl-2,3-dithio)-4′,5′-ethylenedithiotetrathiafulvalene (DOET) with the photochromic anion [Fe(CN)₅NO]^2?, namely, (DOET)₄[Fe(CN)₅ NO]_1.25(C₆H₅Cl)_0.75, is synthesized. Single crystals of this salt are studied using X-ray diffraction [a = 10.398(2) Å, b = 11.168(2) Å, c = 18.499(4) Å, α = 103.14(3)°, β = 92.80(3)°, γ = 106.02(3)°, V = 1996.3(7) ų, space group \(P\bar 1\), and Z = 1]. In the structure, radical cation layers alternate with anion layers along the c axis. The centrosymmetric dimers are formed by DOET radical cations in the donor layer with packing of the β type. Like the vast majority of DOET-based salts, the new salt possesses semiconductor properties.     

Synthesis and structure of oxovanadium(IV) complexes [VO(<Emphasis Type="Italic">Acac</Emphasis>)<Subscript>2</Subscript>] and [VO(<Emphasis Type="Italic">Sal</Emphasis>: <Emphasis Type="Italic">L</Emphasis>-alanine)(H<Subscript>2</Subscript>O)]

Bis(acetylacetonato)oxovanadium C₁₀H₁₄O₅V (I) and (S)-[2-(N-salicylidene)aminopropionate]oxovanadium monohydrate C₁₀H₉NO₅V (II) are synthesized. The crystal structures of compounds I and II are determined using single-crystal X-ray diffraction. Crystals of compound I are triclinic, a = 7.4997(19) Å, b = 8.2015(15) Å, c = 11.339(3) Å, α = 91.37(2)°, β = 110.36(2)°, γ = 113.33(2)°, Z = 2, and space group \(P\bar 1\). Crystals of compound II are monoclinic, a = 8.5106(16) Å, b = 7.373(2) Å, c = 9.1941(16) Å, β = 101.88(1)°, Z = 2, and space group P2₁. The structures of compounds I and II are solved by direct methods and refined to R₁ = 0.0382 and 0.0386, respectively. The oxovanadium complexes synthesized are investigated by vibrational spectroscopy.     

Synthesis and an X-ray diffraction study of Rb<Subscript>2</Subscript>[(UO<Subscript>2</Subscript>)<Subscript>2</Subscript>(C<Subscript>2</Subscript>O<Subscript>4</Subscript>)<Subscript>3</Subscript>]

The synthesis and X-ray diffraction study of compound Rb₂[(UO₂)₂(C₂O₄)₃], which crystallizes in the monoclinic crystal system, are performed. The unit cell parameters are as follows: a = 7.9996(6) Å, b = 8.8259(8) Å, c = 11.3220(7) Å, β = 105.394(2)°, and V = 770.7(1) ų; space group P2₁/n, Z = 2, and R ₁ = 0.0271. [(UO₂)₂(C₂O₄)₃]^2? layers belonging to the AK _0.5 ⁰² T ¹¹ crystal chemical group of uranyl complexes (A = UO ₂ ²⁺ , K ⁰² = C₂O ₄ ^2? , and T ¹¹ = C₂O ₄ ^2? ) are uranium-containing structural units of the crystals. The layers are connected with outer-sphere rubidium cations by electrostatic interactions.     

X-Ray Crystal Structure of <Emphasis Type="Italic">trans</Emphasis>-PdCl<Subscript>2</Subscript>(PPh<Subscript>2</Subscript>C<Subscript>12</Subscript>H<Subscript>7</Subscript>S<Subscript>3</Subscript>)<Subscript>2</Subscript>, a New Morphology

Herein we report the crystal structure of trans-PdCl₂(PPh₂C₁₂H₇S₃)₂, 1, in a different morphology than has previously been reported [Stott et al. (Dalton Trans (4):652–653, 2005]. This structure crystallizes in a P-1 space group with a = 9.4249(19) Å, b = 11.540(2) Å, c = 12.559(3) Å, α = 79.07(3)°, β = 78.04(3)°, γ = 69.44(3)°, Z = 1. The earlier structure possessed a P2₁/n space group. Additionally the terthienyl moieties of 1 demonstrate the anti orientation exclusively while the P2₁/n space group structure has some syn and even syn/anti mixed geometries included.     

Na(H<Subscript>2</Subscript>O)[Mn(H<Subscript>2</Subscript>O)<Subscript>2</Subscript>(BP<Subscript>2</Subscript>O<Subscript>8</Subscript>)]: Crystal structure refinement

The crystal structure of synthetic manganese sodium borophosphate hydrate Na(H₂O)[Mn(H₂O)₂(BP₂O₈)] was refined based on X-ray diffraction data. The compound was prepared by soft hydrothermal synthesis in the MnCl₂-Na₃PO₄-B₂O₃-H₂O system. The unit-cell parameters are a= 9.602(1) Å, c= 16.037(3) Å, sp. gr. P6₅22, Z= 6, D _x = 2.57 g/cm³. The water molecules were found to be statistically distributed in the channels of the mixed anionic paraframework consisting of (BO₄) and (PO₄) tetrahedra and [MnO₄(H₂O)₂] octahedra. The hydrogen atoms of the water molecules coordinated to the Mn²⁺ cations were located and their positional and thermal parameters were refined. The crystal-chemical features of borophosphates of the general formula A _x M(H₂O)₂(BP₂O₈)(H₂O) are considered.     

Crystal chemistry of KCuMn<Subscript>3</Subscript>(VO<Subscript>4</Subscript>)<Subscript>3</Subscript> in the context of detailed systematics of the alluaudite family

The crystal structure of new manganese potassium copper vanadate KCuMn₃(VO₄)₃, which was prepared by the hydrothermal synthesis in the K₂CO₃–CuO–MnCl₂–V₂O₅–H₂O system, was studied by X-ray diffraction (R = 0.0355): a = 12.396(1) Å, b = 12.944(1) Å, c = 6.9786(5) Å, β = 112.723(1)°, sp. gr. C2/c, Z = 4, ρ_calc = 3.938 g/cm³. A comparative analysis of the crystal-chemical features of the new representative of the alluaudite family and related structures of minerals and synthetic phosphates, arsenates, and vanadates of the general formula A(1)A(1)′A(1)″A(2)A(2)′M(1)M(2)₂(TO₄)₃ (where A are sites in the channels of the framework composed of MО₆ octahedra and TО₄ tetrahedra) was performed. A classification of these structures into subgroups according to the occupancy of A sites is suggested.     

Crystal structure of <Emphasis Type="Italic">p</Emphasis>-carboxyphenylhydrazone benzoylacetone

The crystal structure of p-carboxyphenylhydrazone benzoylacetone is determined. The crystals are monoclinic, a = 13.614(4) Å, b = 11.388(2) Å, c = 20.029(6) Å, β = 104.82(2)°, V = 2339(9) ų, Z = 8, space group C2/c, and R = 0.038 for 1622 reflections with I > 2σ(I). The crystal is built of C₁₇H₁₄N₂O₄ neutral molecules that are linked by O-H?O hydrogen bonds between the carboxyl groups into centrosymmetric pseudodimers. The effect of carboxylation of the phenylhydrazone fragment and the position of the carboxyl group on the molecular packing in the crystal is determined. The N(1)-H(1N)?O(1) intramolecular hydrogen bond (N-H, 0.94 Å; H?O, 1.87 Å; N?O, 2.59 Å; and the N-H?O angle, 133°) is formed in the molecule.     

Novel Polyoxovanadate K<Subscript>2</Subscript>ZnV<Subscript>5</Subscript>O<Subscript>14</Subscript>: Crystal Structure and Peculiarities of Crystal Chemistry

A novel structure type has been established as a result of studying a non-merohedral microtwin of polyoxovanadate (K₂ZnV₅O₁₄) by X-ray diffractometry (R = 0.0595). The new compound, synthesized under hydrothermal conditions in the ZnCl₂–K₂CO₃–V₂O₅–H₂O system, is characterized as follows: a = 8.066(5) Å, b = 8.117(5) Å, c = 9.236(5) Å, β = 105.287(5)°, sp. P2₁/m, Z = 2, ρ_calcd = 3.54 g/cm³. Edge-shared five-core “clusters” consisting of vanadium octahedra, between which ZnO₄ tetrahedra (sharing vertices with octahedra) are located, form two-dimensional two-layer anion packets of the (ZnV₅O₁₄)^2– composition, alternating along the c axis with layers of potassium atoms. Structural peculiarities determine the morphology and color of new-phase crystals.     

Absolute structure of La<Subscript>3</Subscript>Ga<Subscript>5</Subscript>SiO<Subscript>14</Subscript> langasite crystals

The absolute structure of La₃Ga₅SiO₁₄ piezoelectric crystals (a = 8.1746(6) Å, c = 5.1022(4) Å, space group P321, Z = 1) with the positive sense of rotation of the plane of polarization is refined using X-ray diffraction analysis (R = 1.37%, R _w = 1.71%, 2413 unique reflections, max sinθ/λ = 1.15 Å^?1). The contributions from the anharmonicity of thermal vibrations of lanthanum atoms are calculated with the use of the components of the third-and fourth-rank tensors. It is demonstrated that these contributions can have a significant effect.     

Synthesis and structure of a terephthalato-bridged nickel complex [Ni(tpt)(imi)<Subscript>3</Subscript>(H<Subscript>2</Subscript>O)]<Emphasis Type="Italic">n</Emphasis>

At room temperature, a new coordination polymer [Ni(tpt)(imi)₃(H₂O)]n was synthesized by the reaction of NiCl₂?6H₂O, terephthalic acid, and imidazole in aqueous solution. The structure was determined by X-ray crystallography. It crystallizes in monoclinicP2₁/n space group with the crystal cell parameters ofa = 9.8626(4) Å,b = 15.2498(3) Å, andc = 12.7681(3)Å, β = 90.309(2)^°,V = 1920.33(10) ų, andZ = 4. The crystal X-ray analysis shows that each nickel atom is coordinated by three imidazole ligands, two terephthalate ions, and one water molecule. Each terephthalate ion bridges two nickel atoms to form a zigzag chain. The chains are further linked together via hydrogen bonds to a three-dimensional network.     

Crystal structure analysis of 4-phenylquinolin-2-(1<Emphasis Type="Italic">H</Emphasis>)-one

The crystal structure of 4-phenylquinolin-2-(1H)-one (C₁₅H₁₁NO) is determined by X-ray diffraction. The compound crystallizes in the orthorhombic crystal system (space group Pbca) with the unit cell parameters a = 7.382(2) Å, b = 21.795(3) Å, c = 14.066(5) Å, and Z = 8. The structure is solved by direct methods and refined to an R-value of 0.0398 for 1360 observed reflections [F₀ > 4σ (F₀)]. The quinoline moiety and the substituted phenyl ring are nearly planar. The dihedral angle between these two moieties is 64.65(6)°. The crystal structure is stabilized by two intermolecular N-H?O and C-H?O interactions.     

Crystal structure and microtwinning of monoclinic La<Subscript>3</Subscript>SbZn<Subscript>3</Subscript>Ge<Subscript>2</Subscript>O<Subscript>14</Subscript> crystals of the langasite family

The crystal structure of monoclinic La₃SbZn₃Ge₂O₁₄ crystals from the langasite family is determined by X-ray diffraction analysis [a = 5.202(1) Å, b = 8.312(1) Å, c = 14.394(2) Å, β = 90.02(1)°, sp. gr. A2, Z = 2, and R/R _w = (5.2/4.6)%]. The structure is a derivative of the Ca₃Ga₂Ge₄O₁₄-type structure (a = 8.069 Å, c = 4.967 Å, sp. gr. P321, Z = 1). The crystal studied is a polysynthetic twin with the twin index n = 2, whose monoclinic components are related by pseudomerohedry by a threefold rotation axis of the supergroup P321.     

Synthesis and structure of (Rb<Subscript>0.50</Subscript>Ba<Subscript>0.25</Subscript>)[UO<Subscript>2</Subscript>(CH<Subscript>3</Subscript>COO)<Subscript>3</Subscript>]

A new compound (Rb_0.50Ba_0.25)[UO₂(CH₃COO)₃] is synthesized and its crystal structure is studied by X-ray diffraction. The compound crystallizes in the form of yellow plates belonging to the cubic crystal system. The unit cell parameter a = 17.0367(1) Å, V = 4944.89(5) ų, space group I \(\bar 4\)3d, Z = 16, and R = 0.0182. The coordination polyhedron of the uranium atom is a hexagonal bipyramid with oxygen atoms of three acetate groups and the uranyl group in the vertices. The crystal chemical formula of the uranium-containing group is AB ₃ ⁰¹ (A = UO ₂ ²⁺ , B ⁰¹ = CH₃COO^?). The oxygen atoms of the acetate groups that enter the coordination polyhedron of uranium are bound to barium and rubidium atoms.     

Structural study of new compound Bi<Subscript>2.53</Subscript>Li<Subscript>0.29</Subscript>Nb<Subscript>2</Subscript>O<Subscript>9</Subscript> by the powder neutron diffraction method

A new compound of composition Bi_2.53Li_0.29Nb₂O₉ was synthesized in the course of the search for new materials with high ionic conductivity. Its crystal structure was determined from the neutron diffraction data. The new compound Bi_2.53Li_0.29Nb₂O₉ is crystallized in the orthorhombic system, sp. gr. Cmc2₁, and unit-cell parameters a = 24.849(1) Å, b = 5.4536(3) Å, and c = 5.4619(2) Å at T = 290 K (a = 24.843(2) Å, b = 5.4456(5) Å, and c = 5.4546(5) Å at T = 10 K). Within the temperature range 10–870 K, no structural phase transitions were revealed. The atomic coordinates and the thermal factors in the isotropic approximation were refined by the Rietveld method at 290 and 10 K. The data obtained were analyzed based on the calculated local balance of bond strengths.     

The Influence of Cation Substitution on the Kinetics of Phase Transitions in Crystals of (K,NH<Subscript>4</Subscript>)<Subscript>3</Subscript>H(SO<Subscript>4</Subscript>)<Subscript>2</Subscript> Solid Solutions

The structure of (K_0.967(NH₄)_0.033)₃H(SO₄)₂ crystals, belonging to the K₃H(SO₄)₂–(NH₄)₃H(SO₄)₂–H₂O salt system, has been investigated by X-ray structural analysis. The room-temperature characteristics of the atomic structure of these crystals are found to be as follows: sp. gr. C2/c, Z = 4, a = 14.7025(4) Å, b = 5.6859(2) Å, c = 9.7885(3) Å, and R/wR = 0.021/0.030%. The thermal and optical properties of (K,NH₄)₃H(SO₄)₂ and K₃H(SO₄)₂ single crystals have been investigated and compared in a temperature range of 295–500 K.     

Synthesis and characterization of a lead(II) complex [Pb(phen)(H<Subscript>2</Subscript>O)(NO<Subscript>3</Subscript>)<Subscript>2</Subscript>] (phen = 1,10-phenanthroline)

The monomeric lead(II) complex, [Pb(phen)(H₂O)(NO₃)₂] was prepared by a hydrothermal reaction of Pb(NO₃)₂, nitrilotriacetic acid, NaOH, 1,10-phenanthroline, and H₂O. The structure was determined by X-ray crystallography. It crystallizes in monoclinic P2(1)/n space group with the crystal cell parameters of a = 6.3568(6), b = 20.2345(19), c = 11.2722(9) Å, β = 98.337(4)^°, V = 1434.6(2) ų, and Z = 4. The crystal X-ray analysis shows that the lead atom is six-coordinated by two N atoms of phen ligand, three oxygen atoms of nitrate anions and one water molecule. Owing to the presence of a lone pair of electrons of lead atom, a significant gap occurs in the coordination geometry around Pb ion. A 3D architecture is formed through the strong hydrogen bonding and π–π stacking interactions.     

Crystal structure of Rb<Subscript>2</Subscript>Mn<Subscript>3</Subscript>(H<Subscript>2</Subscript>O)<Subscript>2</Subscript>[P<Subscript>2</Subscript>O<Subscript>7</Subscript>]<Subscript>2</Subscript>, a new representative of the family of hydrated diphosphates

The crystal structure of Rb₂Mn₃(H₂O)₂[P₂O₇]₂, a new phase obtained in the form of single crystals under hydrothermal conditions in the MnCl₂–Rb₃PO₄–H₂O system, is determined by X-ray diffraction (Xcalibur-S-CCD diffractometer, R = 0.0270): a = 9.374(2), b = 8.367(2), c = 9.437(2) Å, ß = 99.12(2)°, space group P2₁/c, Z = 2, D_x = 3.27 g/cm³. A correlation between the unit-cell parameters and the size of cations forming the crystal structures of isostructural A₂M₃(H₂O)₂[P₂O₇]₂ diphosphates (A = K, NH₄, Rb, or Na; _M = Mn, Fe, Co, or Ni) is revealed. It is shown that, due to the topological similarity, the structures of diphosphates and orthophosphates of the farringtonite structural type can undergo mutual transformations.     

Low-temperature X-ray diffraction studies of [(CH<Subscript>3</Subscript>)<Subscript>2</Subscript>NH<Subscript>2</Subscript>]<Subscript>5</Subscript>Cd<Subscript>3</Subscript>Cl<Subscript>11</Subscript> crystals

[(CH₃)₂NH₂]₅Cd₃Cl₁₁ crystals are grown by the method of isothermal evaporation from saturated aqueous solutions containing dimethylamine and cadmium chlorides, [(CH₃)2NH₂]Cl and CdCl_2.5H₂O. The crystal grown are studied by the X-ray diffraction method. It is established that the crystals are orthorhombic with the unit-cell parameters at room temperature a = 18.115 ± 0.004 Å, b = 11.432 ± 0.002 Å, and c = 15.821 ± 0.003 Å. The unit-cell parameters a, b, and c of the [(CH₃)₂NH₂]₅Cd₃Cl₁₁ crystals are measured as functions of temperature in the temperature range 100–320 K. The data obtained were used to determine the thermal expansion coefficients along the main crystallographic axes. The temperature curves of the unit-cell parameters and thermal expansion coefficients showed pronounced anomalies in the vicinity of the temperatures T ₁ = 120, T ₂ = 150, and T ₃ = 180 K corresponding to the phase transitions in the [(CH₃)₂NH₂]₅Cd₃Cl₁₁ crystals. The crystals are also characterized by a pronounced anisotropy of thermal expansion.