Crystal structure of NH3(CH2)2NH3BiCl5·2H2O

The ethylenediammonium pentachlorobismuthate(III) dihydrate salt is monoclinic with the following unit cell dimensions: a = 10.902(8)Å, b = 7.926(6)Å, c = 15.199(6)Å, = 96.40(1)°, space group P2₁/n with Z = 4. The structure shows a layer arrangement parallel to the axis: planes of the [Bi₂Cl₁₀]^4– bioctahedra alternate with planes of [NH₃(CH₂)₂NH₃]²⁺ dications. The [Bi₂Cl₁₀]^4– bioctahedra are connected through O(W)–H··· Cl hydrogen bonds, so that infinite unidimensional chains of composition [Bi₂Cl₁₀(H₂O)₂] _n ^4n– are formed in the structure parallel to the axis. These chains are themselves interconnected by means of the N–H···Cl bonds originating from the [NH₃(CH₂)₂NH₃]²⁺ entities, forming a three-dimensional network.     

The molecular structure of the diacetic acid adduct of guanidinium tetrabromochromate(II)

The diacetic acid adduct of guanidinium tetrabromochromate(II) crystallizes in the monoclinic crystal system:a=8.778,b=9.125,c=12.195 Å,=89.84°, space groupP2₁/n,Z=2. The structure was determined using the heavy atom method followed by Fourier methods and refined by full-matrix least-squares toR=0.061 for 2221 observed reflections. The structure contains discrete [CrBr₄(HO₂CCH₃)₂]^2– anions separated by [C(NH₂)₃]⁺ cations. The chromium(II) atom is six-coordinate withtrans pairs of Cr-Br bonds of unequal length (2.84 and 2.63 Å), and two acetic acid molecules completing the coordination.     

Tetrahedral complexes of 1,2-dimorpholinoethane and 1,3-dimorpholinopropane: Crystal and molecular structure of dichloro(1,2-dimorpholinoethane)cobalt(II)

The ligands 1,2-dimorpholinoethane (DME) and 1,3-dimorpholinopropane (DMP) have been used to prepare Cu(II), Ni(II), Co(II), Hg(II), Zn(II), and Cd(II) complexes having the general formulationMLX ₂ (L=DME and DMP,X=Cl^–). These complexes exhibit spectral properties indicative of a distorted tetrahedral geometry, with DME or DMP coordinating through two nitrogen atoms and two chloride anions making up the coordination sphere of the central metal atom. This is in contrast to six-coordinated, distorted octahedral geometry exhibited by metal complexes of DME when NO ₂ ^– or NO ₃ ^– were used as counter ions. The tetrahedral geometry was confirmed for [Co(DME)Cl₂] by X-ray structure determination. The structure was solved by the heavy-atom method using CAD4 diffractometer data, and refined to a finalR value of 0.028 for 1097 independent reflections. The morpholine moieties of DME in [Co(DME)Cl₂] are in a chair configuration, forbidding any coordination through ethereal oxygen atoms.     

Crystal structure of triethylentetraammonium bis monohydrogen-monophosphate dihydrate β-NH3(CH2)2NH2(CH2)2NH2(CH2)2NH3(HPO4)2·2H2O

The salt triethylentetraammonium bis monohydrogen-monophosphate dihydrate is orthorhombic Pbca with unit cell dimensions a = 8.963(2), b = 10.326(2), c = 17.381(4)Å; Z = 4; D_m = 1.540 g cm^–3; D _x = 1.562 g cm^–3. The examination of the structure shows a layer arrangement parallel to the axis: planes of [HPO₄]^2– tetrahedra alternate with planes of [(NH₃(CH₂)₂NH₂CH₂)₂]⁴⁺. The [HPO₄]^2– tetrahedra are connected through O(W)s--H···O hydrogen bonds, so that infinite chains of the composition [HPO₄(H₂O)]_n ^2n– are formed in the structure parallel to the axis. The structure of this compound is built from [HPO₄]^2– anions, [(NH₃(CH₂)₂NH₂CH₂)₂]⁴⁺ cations and zeolitic water molecules connected by hydrogen bonds.     

Growth, refined structural and spectroscopic characteristics of Tm-doped NaGd(WO4)2 single crystals

The details of Tm³⁺-doped NaGd(WO₄)₂ single-crystal growth are discussed, the results of precise investigations of its structural and spectroscopic characteristics, as well as the analysis of cross-relaxation process of Tm³⁺ ions (³H₄→³F₄, ³H₆→³F₄) in this crystal are presented. Based on the Judd–Ofelt theory, three intensity parameters, spontaneous emission probabilities, fluorescence branching ratios and fluorescence quantum efficiency from ³H₄ and ³F₄ levels were refined.     

Crystal structure of lithium magnesium phosphate,LiMgPO4: Crystal chemistry of the olivine-type compounds

LiM_gPO₄ is orthorhombic, space groupPnma,a=10.147(2),b=5.909(2),c=4.692(2)×10^–10 m,D _m =3000(8),D _x =2980 kg m^–3,Z=4,R=4.8% for 1262 observed reflections. The structure contains tetrahedral PO₄ and octahedral LiO₆ and MgO₆ groups. It belongs to the ordered olivine-type structures, since the inversion site is occupied by Li⁺ ions and the mirror site is taken by Mg²⁺ ions. The distortion of polyhedra is caused mainly by the adjustment stresses between the different polyhedral dimensions and by the sharing of edges. Octahedral LiO₆ share six and MgO₆ share three common edges. The sharing of the O-O edges contributes to the stability of the bridging arrangements. The corresponding average distances of the O-O bridges are 2.432, 2.479, 2.883, and 3.028×10^–10 m, while the average O-O distances in the PO₄, MgO₆, and LiO₄ polyhedra are 2.512,2.921, and 3.015 × 10^–10 m, close to the ideal values 2.531, 2.970, and 3.026×10^–10 m respectively. The structure field of the olivine-type compounds plotted as a function of ionic radii in radius space is specified in relation to the-K₂SO₄, spinel, and K₄NiF₄ type structures. From the overlap of the structure fields, the high-pressure transformations of the olivine compounds are considered.     

Crystal structure and spectroscopy of bis-[bis(2-benzimidazolyl)propane]copper(II) bis(triflate)monohydrate, a copper complex with a geometry intermediate between tetrahedral and square planar

The structure of a mononuclear copper(II) compound with the ligand bis(2-benzimidazolyl)propane (abbreviated as tbz) is reported. The compound [Cu(tbz)₂](CF₃SO₃)₂(H₂O) crystallizes in the triclinic space group P , with a = 12.363(6), b = 13.218(9), c = 15.365(8) Å, = 82.74(5), = 68.04(4), = 65.30(5), and Z = 2. The Cu(II) atom has a geometry intermediate between tetrahedral and square planar, consisting of four nitrogen atoms of two tbz ligands. The Cu—N—Cu angles are about 135°, while the dihedral angle between them amounts to 62° (0° for square planar and 90° for a tetrahedron). Ligand field bands are observed at 10.2 × 10³, 13.8 × 10³, and 20.3 × 10³ cm^–1, while the most characteristic infrared vibrations of the triflate anion are observed at 1273, 1260, 1238, 1221, 1171, and 1157 cm^–1.     

The molecular structure of acetato[2-(pyridin-2′-yl)phenyl]mercury(II)

The crystal structure of the title compound was determined by X-ray crystallography. The compound crystallizes in the monoclinic crystal system witha=8.152(4),b=17.994(7),c=8.634(9) Å, =108.92(5)°, space group P2₁/c (N:14),V=1198.02 ų,Z=4. The mercuryl(II) atom forms two strong, almost colinear bonds (bond angle 176.1(4)°) with a carbon of the phenyl ring (Hg–C=1.99(1) Å) and one of the acetate oxygen atoms (Hg–O(1)=2.005(7) Å). These primary bonds are supplemented by secondary intramolecular interactions with the pyridine nitrogen (Hg...N=2.727(9) Å) and the other acetate oxygen (Hg...O(2)=2.925(8) Å), although the latter is very weak and the acetate anion therefore practically monodentate. Weak additional intermolecular Hg–C and Hg–O(1)interactions contribute to the lattice structure.     

Structure and spectral properties of 10-(3-dimethylaminopropyl)phenothiazinium chloride and Reinecke salts

The IR and visible spectra of HPromazine⁺ deuteroreineckate^–, DPromazine⁺ reineckate^– and HPromazine⁺ reineckate^–, reineckate^– is Cr(NCS)₄(NH₃) ₂ ^– are reported together with the X-ray crystal structure determination of the latter. The assignment of the IR bands and the visible spectra are discussed in conjunction with the X-ray data. There is extensive hydrogen bonding in crystalline HPromazine⁺ reineckate^– and the influence of the hydrogen bonding on the dimensions of the reineckate^– anion is discussed. The folding of the phenothiazine ring in various derivatives is analyzed.     

Growth and spectroscopic characteristics of Er:YbVO4 crystal

A laser crystal Er³⁺:YbVO₄ has been grown by the Czochralski method with excellent quality. The rocking curve from the (0 0 4) diffraction plane of the as-grown Er³⁺:YbVO₄ crystal was measured and the full-width at half-maximum value was found to be 19.80 in. for the (0 0 4) face. The effective segregation coefficient of Er³⁺ was studied by X-ray fluorescence and the crystal structure was determined by means of X-ray diffraction analysis. The polarized absorption spectra and the fluorescence spectra of Er³⁺:YbVO₄ were measured at room temperature. The spectral parameters were calculated based on the Judd–Ofelt theory, and the intensity parameters Ω₂, Ω₄ and Ω₆ are found to be 5.50×10⁻²⁰, 1.96×10⁻²⁰ and 2.34×10⁻²⁰ cm², respectively. The emission cross-section has been calculated by the Fuechtbauer–Ladenbury method. The spectroscopic parameters of Er³⁺:YbVO₄ are compared with other typical laser hosts.     

Crystal structure of [Co(o-SC6H4NH2){P(OMe)3}3]PF6

A cobalt-thiolato-phosphite complex [Co(o-SC₆H₄NH₂){P(OMe)₃}₃]PF₆ has been prepared and characterized by X-ray crystallography. The complex crystallizes in the triclinic space group with a = 10.590(4), b = 11.122(3), c = 13.577(5) Å, = 101.85(1), = 108.50(1), = 101.75(1)°, V = 1420.6(8) ų, and Z = 2. The structure comprises discrete [Co(o-SC₆H₄NH₂){P(OMe)₃}₃]⁺ cations and PF ₆ ^– anions where the metal atom is coordinated in a highly distorted square-pyramidal environment by one chelate o-SC₆H₄NH ₂ ^– (abt) and two P(OMe)₃ ligands in the basal positions, and a third P(OMe)₃ in the axial site with Co–N,, 1.847(5), Co–S, 2.166(2), Co–P, 2.157(2), 2.147(2), and 2.125(2) Å.     

Crystal structure of tetrakisdiphenylammonium hexadecachlorotetrabismuthate(III)

[(C₆H₅)₂NH₂]₄ ⁺[Bi₄Cl₁₆]^4– crystallizes in the triclinic space group witha=11.835(2),b=12.393(2),c=12.625(3)Å, =108.37(3), =108.69(3), =96.00(3)° andD _c=2.135 g cm^–3 forZ=1. The [Bi₄Cl₁₆]^4– anion is a centrosymmetric cluster of four distorted edge-sharing BiCl₆ octahedra. The ranges of the Bi–Cl bonds are 2.484(4)–2.606(3)Å for Bi–Cl(terminal), 2.691(3)–2.956(4)Å for Bi-Cl(µ₂), and 2.960(3)–3.120(4)Å for Bi-Cl(µ₃). The cations and anions are held in place by weak hydrogen bonds.     

FTIR, XRD and ac impedance spectroscopic study on PVA based polymer electrolyte doped with NH4X (X = Cl, Br, I)

The present study focuses on characterizing PVA: NH₄X (X = Cl, Br, I) proton conducting polymer electrolyte prepared by solution casting technique using XRD, FTIR and ac impedance spectroscopic studies. The XRD patterns of all the prepared polymer electrolytes reveal the amorphous nature of the films. The FTIR spectroscopic study indicates the detailed interaction of PVA with proton. From ac impedance spectroscopic studies, it has been found that PVA doped with NH₄I have high ionic conductivity (2.5 × 10⁻³S cm⁻¹) than PVA doped with NH₄Br (5.7 × 10⁻⁴S cm⁻¹) and NH₄Cl (1.0 × 10⁻⁵S cm⁻¹) polymer electrolytes. This is due to the large anionic size and low lattice energy of NH₄I (in comparison with NH₄Br and NH₄Cl).The temperature dependence of ionic conductivity for all the PVA: NH₄X (X = Cl, Br, I) polymer films obey Arrhenius equation. Ionic transference number measured has been found to be in the range of 0.93-0.96 for all the polymer electrolytes proving that the total conductivity is mainly due to ions.     

Crystal structure,physical, and photophysical properties of a ruthenium(II) bipyridine diazafluorenone complex

The complex [Ru(bpy)₂(dafo)](PF₆)₂, where bpy is 2,2-bipyridine and dafo is diazafluorenone crystallizes in the space group P2₁/n witha=9.505(3) Å,b=14.002(4) Å andc=25.783(8) Å. The coordination geometry of the Ru atom is that of a distorted octahedron with a RuN₆ core. The two Ru-N bond distances to the dafo ligand are 2.13(1) and 2.15(1) Å; the four Ru-N bond distances to the bipyridine ligands are 2.03(1), 2.05(1), 2.06(1), and 2.07(1) Å. The three shortest Ru-N distances aretrans to the three longest Ru-N distances. The complex is oxidized and reduced reversibly at 1.41 and –0.65 V vs. SSCE, respectively. It displays absorptions at 438 nm (1.6×10⁴), 285 nm (6.2×10⁴), and 240 nm (4.1×10⁴) and a broad emission centered at 626 nm in water at room temperature. The emission lifetime is 420 ns and the emission quantum yield is 5.3×10^–4.     

Crystal growth and spectroscopic properties of erbium doped Lu2SiO5

A high optical quality erbium doped Lu₂SiO₅ single crystal has been grown by the Czochralski method. The distribution coefficient of Er³⁺ was measured to be ∼0.926. The absorption and emission spectra as well as the fluorescence decay curve of the excited state ⁴I_13/2 were measured at room temperature. The spectroscopic parameters were calculated using the Judd–Ofelt theory, and the J–O parameters Ω₂, Ω₄ and Ω₆ were found to be 4.451×10^-20, 1.614×10^-20 and 1.158×10^-20 cm², respectively. The room-temperature fluorescence lifetime of the Er³⁺⁴I_13/2→⁴I_15/2 transition was measured to be 7.74 ms. The absorption and emission cross-section as well as the gain cross-section in the eye-safe regime of 1400–1700 nm were also determined and discussed.     

Crystal structure of mixed rubidium–ammonium hydrogen sulfate Rb0.7(NH4)0.3HSO4 at room temperature

The structure of Rb_0.7(NH₄)_0.3HSO₄ has been determined by X-ray analysis. The mixed compound crystallizes in the monoclinic space group P2₁/n with unit cell parameters a = 14.374(6) Å, b = 4.618(6) Å, c = 14.412(2) Å, = 118.03(2)°, V = 844.4(4) ų, and D _cal = 1.536 g cm^–3 for Z = 8. The mixed compound Rb_0.7(NH₄)_0.3HSO₄ is a chain-based structure. The Rb⁺ and NH₄ ⁺ cations are intercalated between chains, formed of HSO₄ ^- groups linked with OHO hydrogen-bonding. Rb_0.7(NH₄)_0.3HSO₄ presents a new type of structural arrangement different from those of pure RbHSO₄ and NH₄HSO₄.     

Crystal structure and physical properties of a ruthenium(II) bipyridine dimethylsulfoxide complex

The complex [Ru(bpy)₂(DMSO)C1]PF₆, where bpy is 2,2-bipyridine and DMSO is dimethylsulfoxide, crystallizes in the triclinic space group P1¯ (#2) with a = 8.873 (2), b = 12.805 (4), c = 12.864 (4) Å, = 97.76(3), = 106.45(2), = 107.88(2); Z = 2, and d _calc = 1.75 mg/m³. The coordination geometry is that of a distorted octahedron with a cis –RuN₄SCl arrangement of coordinating atoms. The four Ru—N distances to the bpy ligands are 2.082(5), 2.092(4), 2.044(4), and 2.078(5) Å. The Ru—Cl distance is 2.421(2) Å and the Ru—S distance to DMSO is 2.260(1) Å. The Ru—N bond distance trans to Cl is the shortest; the Ru—N bond distance trans to S is the longest. The complex is oxidized and reduced reversibly at 1.13 and –1.37 V vs. SSCE, respectively. It displays electronic absorptions at 515, 480 (1.5 × 10⁴), 342 (1.5 × 10⁴), 292 (1.2 × 10⁵), and 240 nm (6.2 × 10⁴) and has a broad emission band centered at 607 nm at 77 K in a 4:1 ethanol/methanol glass. The emission lifetime at room temperature is less than the pulse width of the laser, < 20 ns.     

Synthesis, spectroscopy, and X-ray structure of the polymer catena-[bis(azido-N)-copper(II)-μ-bis(2-benzimidazolyl)butane]

The title compound, catena-[bis(azido-N)-copper(II)-(bis(2-benzimidazolyl)butane), [Cu(C₁₈H₁₈N₄)(N₃)₂]_n, was obtained from the reaction of the ligand bis(2-benzimidazolyl)butane and Cu(N₃)₂. The x-ray crystal structure is reported. The compound crystallizes in the monoclinic space group P2₁/c with a = 8.2524(10), b = 12.765(5), c = 9.1125(15) Å, = 106.423(12)°, Z = 2. The Cu(II) ions are square-planar coordinated with trans-oriented end-on binding azido ligands. The structure is a polynuclear chain with the benzimidazole bridging at each end. In addition a N_(ligand)-H···N_(azido) H-bridge [N_(ligand)···N_(azido) = 2.994(7) Å] is present, resulting in a pseudo 2-dimensional lattice. The characteristic azido infrared vibrations are found at 2060 and 2077 cm^–1 (_as(N₃)) and 1284 and 1297 cm^–1 ((N₃)).     

Crystal and molecular structure of monoglycine nitrate

The crystal and molecular structure of monoglycine nitrate (C₂ H₆ NO⁺ ₂, NO^– ₃) has been determined by single-crystal X-ray diffraction methods. The crystals are orthorhombic: space groupP2₁2₁2₁,a = 16.42(6),b = 6.10(4),c = 5.61(5) Å andZ = 4. The structure has been solved by direct phase determination methods, using visually-estimated intensity data, and was refined to anR -value of 0.064, using counter-measured intensity data for 660 reflections. The anomalous scattering by oxygen and nitrogen atoms suggests the present configuration.The molecule in the structure exists as⁺NH₃CH₂CO₂H, NO^– ₃. The glycinium molecule is planar, except for the N(amino) atom, which deviates by 0.48 Å from the molecular plane defined by the atoms C(1), C(2), O(1) and O(2). The torsion angle N(1), C(2), C(1), O(1) is 20.7 °. The NH₃ group is a donor of three hydrogen bonds of equal strength (N ... 0 = 2.85 Å). Two of the hydrogen atoms of the NH₃ group also form weak bifurcated hydrogen bonds (N ... 0 = 3.04 Å). One of the carboxyloxygen atoms is a donor of a hydrogen bond (0 ... 0 = 2.65 Å). The oxygen atom of the carboxyl group and the oxygen atoms of the nitrate group are all acceptors of hydrogen bonds.The major part of this work was carried out at the Max-Planck Institute for Biochemistry, Martinsried (Munich), and one of the authors (P.N.) expresses his gratitude to Prof. W. Hoppe and his group for the facilities made available to him and for their help. He is also grateful to the Max-Planck Gesellschaft for the award of a research fellowship.     

Self-assembly in transition metal complexes: structural characterization of a copper histamine nitrate [Cu(II)(him)2(NO3)2]

A new monomeric copper (II) complex with histamine (him), [Cu(II)(him)₂(No₃)₂], has been prepared by the reaction of Cu(NO₃)₂ with histaminium dichloride and its structure was determined by x-ray crystallography. The complex crystallizes in the triclinic system, space group with a = 5.7238(4), b = 8.7094(7), c = 9.2481(11) Å, = 69.693(8), = 73.242(7), = 71.050(7)°, V = 400.84(6) ų, and Z = 1. The structure consists of discrete [Cu(II)(him)₂(NO₃)₂] molecules in which the metal atom is centrosymmetrically coordinated by two histamine ligands forming an equatorial plane with Cu–N(imidazole ring) being 2.032(2) and Cu–N(NH₂ group) being 2.023(2) Å. Two O atoms from nitrate anions coordinate on the elongated axial positions with Cu–O being 2.549(2) Å. In the crystal structure, the molecules are organized by hydrogen bonds forming a two-dimensional network.