Zeitschrift für Kristallographie

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A dihydropyrimidine (DHPM) derivative was synthesized, characterized by X-ray diffraction and searched in silico for its inhibitory activities against AccD5 enzyme, the CT domain of a Mycobacterium tuberculosis ACCase. Its molecular structure was compared to another DHPM derivative (DHPM II ). The results have shown that the (±)2,6-methano-4-thioxo-3,4,5,6-tetrahydro-2H-[1,3,5] benzoxadiazocines (DHPM I) and (±)2,6-methano-4-oxo-3,4,5,6-tetrahydro-2H-[1,3,5] benzoxadiazocines (DHPM II) belong to the monoclinic and triclinic systems, respectively, and their crystal structures are stabilized by N–H⋯O, O–H⋯O and N–H⋯S interactions. The DHPM derivatives established hydrogen bond interactions with the oxyanion-stabilizing residues (Gly-434/Ala-435) beyond the Thr-217, Phe-394 and Ile-216 in the biotin pocket. The predicted MoB of the DHPM derivatives (21R, 24S, 22R) configuration showed that its phenyl moiety was positioned on the interface between the biotin and propionyl-CoA pockets, suggesting a possible blockade of both subsites. Additionally, the hydrogen bonds involving the O-bridged phenyl ring of the DHPM derivatives (21S, 24R, 22S) configuration with Gly434 in the oxyanion-stabilizing region placed its phenyl moiety in the bottom of the biotin pocket establishing hydrophobic interactions with Leu164, Tyr167, Val459 and Ala155. These results indicate the DHPM derivatives as potential AccD5 inhibitors and promising starting points for future optimizations. Although the overlap of DHPM I and DHPM II did not present significant differences, the exchange of a sulfur atom for an oxygen atom increased the predicted biological potential.
 
Data collection and handling.
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 ).
C14H 26 N4S4, monoclinic, C2/c (no. 15), a = 16.9951(10) Å, b = 11.4397(7) Å, c = 9.7678(6) Å, β = 103.913(1)°, V = 1843.33(19) Å 3 , Z = 4, Rgt(F) = 0.0200, wR ref (F 2) = 0.0553, T = 100(2) K.
 
Uranyl sulfate minerals occur as common alteration products after hydration-oxidation weathering of uraninite in oxide zones of most uranium deposits [1], [2], [3]. Among the most common uranyl sulfates we can find minerals of the zippeite group; the members of this mineral group are paragenetically, chemically [2], [3], [4] and structurally related [5], [6], [7]. Mineral members of this group are hydrated uranyl oxide-hydroxo-sulfates, which contain monovalent (K, Na or NH4+), divalent (Mg, Zn, Co, Ni or Cu) or trivalent (Y or rare-earth elements, REE3+) cations. Their structures are composed of sheets of UO7 and SO4 polyhedra, with characteristic topology, i.e. zippeite topology [6], with U:S ratio 2:1; the OH/O content within the sheet is variable. The overall symmetry of the structures varies from triclinic to orthorhombic. In the interlayer, hydrated cations and molecular H2O are located. A periodicity of stacking of layers, reflected in one of the unit-cell parameters (b; in case of monoclinic zippeites), depends on the cationic content and ordering of the metal cations in interlayer, as has been suggested by structure studies on several synthetic compounds and natural minerals [5], [8]. Here, we report on the twinned structure of the mineral zippeite, recently found at Cap Garonne, Var, France. This is the second structure-determination from natural crystal.
 
The DSC curves in heating/cooling mode for 1, 2 and 3 single crystals. 
The difference of electron density map around the M4-site is the crystal structures of Ca 9 Y(VO 4 ) 7 (1), Ca 9 Y(VO 4 ) 7 :Li (2), Ca 9 Y(VO 4 ) 7 :Mg (3). Contour intervals are 0.1 eÅ −3 . 
Single crystals of Ca9Y(VO4)7 (1), Ca9Y(VO4)7:Li⁺ (2) and Ca9Y(VO4)7:Mg²⁺ (3) were grown by the Czochralski method. Their chemical composition was analyzed by ICP spectroscopy and their crystal structure was examined by single crystal X-ray analysis. The crystals are characterized by trigonal symmetry, space group R3c. Hexagonal unit-cell parameters are as follows: a=10.8552(1) Å, c=38.0373(2) Å, V=3881.65(1) ų for 1; a=10.8570(1) Å, c=38.0161(3) Å, V=3880.77(4) ų for 2; a=10.8465(1) Å, c=38.0366(2) Å, V=3875.36(3) ų for 3. All crystals are characterized by β-Ca3(PO4)2-type structure with statistical distribution of Ca²⁺ and Y³⁺ over M1, M2 and M5 sites in different ratios and with completely empty M4-cationsite. The impurity of Mg²⁺cations in structure 2 has been detected in octahedral M5 site. Ferroelectric phase transitions are evidenced by DSC and SHG. At about 1220 and 1300 K, they demonstrate phase transitions. Upon heating the symmetry of the crystal structure changes according to the scheme R3c→R3̅c→R3̅m and is restored during consequent cooling. The first of them is of ferroelectric and the second of non-ferroelectric nature. Even a small amount of impurities in Ca9Y(VO4)7 structure is accompanied by a noticeable decrease in the temperature of the ferroelectric-paraelectric phase transition.
 
The uranyl mineral swamboite has been redefined to swamboite-(Nd) and its structure has been solved and refined as a commensurate structure in sixdimensional superspace. The structure is monoclinic, superspace group P21/m(a1, b1, g1)00(−a1, b1, g1)00(a2,0,g2)0s, cell parameters a = 6.6560(3), b = 6.9881(5), c = 8.8059(6), c = 11.3361(16) Å, β = 102.591(5)°, modulation wave-vectors q1 = 1/3 1/3 0; q2 = −1/3 1/3 0; q3 = 1/2 0 1/2. The structure was refined from 8717 reflections to a final R = 0.0610. The model includes modulation both of atomic positions and displacement parameters, as well as occupancy waves. The structure is based upon uranyl-silicate sheets of uranophane topology alternating with an interlayer of partly occupied Nd3+ sites and H2O molecules. The strong (3 + 3) dimensional modulation of the structure originates from the distribution of the Nd-dominated sites and further accommodation of the suitable geometry within the sheets and charge distribution within the structure. The separation distances between the corresponding occupied Nd sites are rationals of the super-cell vectors corresponding to the modulation vectors of the structure. The case of swamboite-(Nd) is the first example of a modulated structure within the oxysalts of U6+.
 
Mn ²⁺ -bearing eleonorite from the Hagendorf South pegmatite situated south of Waidhaus, Upper Palatinate, Bavaria, Germany was study based on single crystal X-ray analysis, Mn and Fe K -edge XANES spectroscopy, as well as IR spectroscopy. According to spectroscopic data, all Mn is bivalent, and all Fe is trivalent. The empirical formula of the mineral is (Mn ²⁺0.58 Zn 0.13 Mg 0.04 Fe ³⁺5.24 ) Σ5.98 (PO 4 ) 4 (H 2 O,OH,O) 11 . The monoclinic unit-cell parameters are: a =20.832(3) Å, b =5.1569(3) Å, c =19.200(2) Å, β=93.01(1)°; space group C 2/ c . The structure was refined to R1 =5.20% in anisotropic approximation using 1994 reflections with I >3σ( I ). Despite in most beraunite-group minerals M 1-site demonstrates selective accumulation of bivalent cations, in Mn-bearing eleonorite Mn ²⁺ -cations are disordered between octahedral sites without statistical predominance anywhere; all octahedral M (1–4)-sites are predominantly occupied by Fe ³⁺ . M 1-site is half-occupied by Fe ³⁺ and contains subordinate Mn ²⁺ and minor Zn ²⁺ and Mg ²⁺ . Based on the new data we suppose that Mn-bearing eleonorite was formed as a secondary phase as a result of oxidation of a primary Mn-bearing beraunite-group mineral in with Mn ²⁺ was initially distributed between different M sites.
 
The first uranyl beryllophosphate, [(UO2)2{Be(H2O)2(PO4)2}]∙(H2O), has been synthesized under hydrothermal conditions at 200°C. The monoclinic unit-cell parameters are: a = 9.3361(1), b = 8.8545(4), c = 9.6583(4) Å, β = 93.227(4)°, V = 797.15(6) Å3, space group P2/n, Z = 2. The crystal structure has been solved by direct methods and refined to final R1 = 4.92% using 1294 I > 3σ(I) reflections in the anisotropic approximation. The structure consists of sheets of UrO5 pentagonal bipyramids and PO4 tetrahedra. UrO5 bipyramids are linked by edge-sharing to form infinite chains. Adjacent chains of UrO5 bipyramids are connected by sharing alternating edges of uranyl bipyramids with PO4 tetrahedra. The resulting sheets are based on the well-known uranophane anion-topology. Be atoms are tetrahedrally coordinated by two oxygen atoms of PO4 tetrahedra and two water molecules in the interlayer space. One isolated water molecule also occurs in the interlayer space, where it is held in position by H bonds. The connection between the phosphorus and beryllium tetrahedra leads to formation of an unbranched trimer [BeP2O8(H2O)2]4- observed for the first time in inorganic oxysalts.
 
Vanuralite, Al[(UO2)2(VO4)2](OH) · 8.5H2O, is a rare supergene uranyl vanadate that forms during hydration- oxidation weathering of uraninite in oxide zones of U deposits. On the basis of single-crystal X-ray diffraction data it is monoclinic, space group P21/n, with a = 10.4637(10), b = 8.4700(5), c = 20.527(2) Å, β = 102.821(9)°, V = 1773.9(3) Å3 and Z = 4, Dcalc. = 3.561 g cm−3. The structure of vanuralite (R = 0.058 for 2638 unique observed reflections) contains uranyl vanadate sheets of francevillite topology of the composition [(UO2)2(VO4)2]2−. Sheets are stacked perpendicular to c, and an interstitial complex [6]Al(OH)(H2O)4(H2O)4.5; adjacent structural sheets are linked through an extensive network of hydrogen bonds. Vanuralite is the most complex mineral among uranyl vanadates, with 961 bits/cell. The scarcity of occurrences is probably caused by the less common combination of elements present in the structure, as well as the relatively high complexity of the structure (compared to related minerals), arising namely from the complicated network of H-bonds.
 
C16H18N2O3, orthorhombic , Pca21 (no. 29), a=14.3074(1) Å, b=8.5321(1)Å, c=12.2534(2)Å, V =1495.8(4)Å3, Z =4, Rgt(F)= =0.071, wRref(F2)=0.1266, T =302 K.
 
C14H14N2O2, orthorhombic, P212121 (no. 19), a=5.6736(2) Å, b=7.7803(4) Å, c=28.7821(13) Å, V =1270.5(1) Å3, Z =4, Rgt(F)=0.0454, wRref(F2)=0.0879, T =298 K.
 
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 ). 
C16H15NO5, monoclinic, P21/n (no. 14), a = 6.7689(5) Å, b = 45.219(3) Å, c = 10.1102(6) Å, β = 101.360(7)°, V = 3033.9(4) ų, T = 298(2) K.
 
C15H16N2O3, monoclinic, P21/c (no. 14), a=11.223(2) Å, b=11.9339(5) Å, c=11.945(2) Å, �=117.43(2)°, V = 1419.9(5) Å3, Z =4, Rgt(F)=0.0528, wRref(F2)=0.1346, T =300(2) K.
 
A new fluorine-dominant titanium calcium amphibole (FTCA) was found in alkali basalts of the Rothenberg volcano situated in the Eifel paleovolcanic region, Rhineland-Palatinate (Rheinland-Pfalz), Germany. The empirical formula based on 24 (O+F) atoms is (Na0.65K0.30)(Ca1.95Na0.05)(Mg3.36Fe3+0.87Fe2+0.13Ti0.60)(Si5.92Al2.08)O22(F1.11O0.89). The crystal structure has been studied based on single-crystal X-ray diffraction data. The monoclinic unit-cell parameters are: a=9.8684(2) Å, b=18.0457(3) Å, c=5.3113(1) Å, β=105.543(3)°; space group C2/m. The structure was refined to R=3.39% in anisotropic approximation using 3661F>4σF. The studied mineral is the first representative of F-dominant amphiboles with CTi>0.5. It is considered as a F-dominant analogue of ferri-kaersutite NaCa2[Mg3Fe3+Ti](Si6Al2O22)O2.
 
Chloride derivatives of lanthanoid(III) oxidotungstates(VI) with the formula Ln3Cl3[WO6] represent an interesting class of compounds, due to their isolated trigonal prismatic [WO6]6− units and their abilities to host active cations for luminescence applications. The attempt to extend the existence range of this series to the dysprosium compound by annealing equivalent amounts of DyCl3, Dy2O3 and WO3 with LiCl as fluxing agent at 750 °C in evacuated silica ampoules for two days resulted in colourless, needle-shaped single crystals of Dy2WO6 instead of the intended dysprosium(III) chloride oxidotungstate(VI) with the formula Dy3Cl3[WO6].
 
(continued) 
C23H30FN5O6, monoclinic, P21/n (no. 14), a = 9.5772(3) Å, b = 15.9466(5) Å, c = 15.8380(5) Å, β = 103.951(1)°, V = 2347.49(13) Å3, Z = 4, Rgt(F) = 0.0423, wR(F2) = 0.192, T = 150 K.
 
(a) Rietveld refinement of the neutron diffraction data collected at 1.5 K ( R nucl =   4.43 %, R mag =   2.81 %). The open symbols (red) and the solid line (black) represent the experimental and calculated intensities, respectively, and the line below (blue) is the difference between them. Tick marks (green) indicate the positions of Bragg peaks ( Pnma space group): nuclear (top), and magnetic k =   0 (bottom). (b) Neutron diffraction patterns at the vicinity of the strongest magnetic peaks collected at different temperatures. (c) Crystal and magnetic structures of Bi 0.65 La 0.35 Fe 0.5 Sc 0.5 O 3 . The primary G z and the secondary A x / F y modes are shown as red and blue arrows respectively. 
Magnetization as a function of temperature, measured for Bi 0.65 La 0.35 Fe 0.5 Sc 0.5 O 3 under the magnetic field of H = 100 Oe after cooling in this field (top). Magnetization loop measured at 5 K after a zero-field cooling (bottom).
X 5 + ( a , a , 0, 0, 0, 0) displacement mode (black arrows on the oxygen ions) coupling the G x (red arrows on the Fe/Sc ions) and C y (blue arrows on the Fe/Sc ions) magnetic order parameters (left). M 3 + (0, m , 0) displacement mode (black arrows on the oxygen ions) coupling the G x (red arrows on the Fe/Sc ions) and A Z (blue arrows on the Fe/Sc ions) magnetic order parameters (right). 
X 5 + ( a , a , 0, 0, 0, 0) displacement mode (black arrows on the oxygen ions) coupling the G y (red arrows on the Fe/Sc ions) and C x (blue arrows on the Fe/Sc ions) magnetic order parameters (left). R 4 + ( r , − r , 0) displacement mode (black arrows on the oxygen ions) coupling the G y (red arrows on the Fe/Sc ions) and F z (blue arrows on the Fe/Sc ions) magnetic order parameters (right). 
M 3 + (0, m , 0) displacement mode (black arrows on the oxygen ions) coupling the G z (red arrows on the Fe/Sc ions) and A x (blue arrows on the Fe/Sc ions) magnetic order parameters (left). R 4 + ( r , − r , 0) displacement mode (black arrows on the oxygen ions) coupling the G z (red arrows on the Fe/Sc ions) and F y (blue arrows on the Fe/Sc ions) magnetic order parameters (right). 
Neutron powder diffraction measurements on the 35 % La-substituted Bi[1−x]La[x]Fe[0.5]Sc[0.5]O[3] composition revealed that the samples obtained under high-pressure (6 GPa) and high-temperature (1500 K) conditions crystalize into a distorted perovskite structure with the orthorhombic Pnma symmetry and the unit cell parameters: ao = 5.6745(2) Å, bo = 7.9834(3) Å and co = 5.6310(2) Å. A long-range magnetic ordering takes place below 220 K and implies a G-type magnetic structure with the moments 4.10(4)μB per Fe aligned predominately along the orthorhombic c-axis. The space group representation theory using the orthorhombic symmetry yields four bi-linear coupling schemes for the magnetic order parameters imposed by antisymmetric exchange interactions. The couplings are analysed based on symmetry adapted distortion modes defined in respect of the undistorted cubic perovskite structure. The approach allows a quantitative estimation of the coupling strength. It is shown that the experimentally found spin configuration combines the magnetic order parameters coupled by the atomic displacement modes with the largest amplitudes. The results indicate that the antisymmetric exchange is the dominant anisotropic term which fully controls the direction of the Fe3+ spins in the distorted perovskite lattice.
 
Crystal packing of (I). Hydrogen bonds are shown as dotted lines. 
The crystal structures of two closely related compounds, namely, N-(4-fluorobenzoyl)-benzenesul- fonamide (I) and N-(4-fluorobenzoyl)-4-methylbenzenesulfonamide (II) are investigated by analysing the packing patterns and intermolecular interactions, and also by Hirshfeld surface analysis. The crystal structure of each of (I) and (II) displays a two-dimensional architecture. Hirshfeld surfaces comprising dnorm surface and 2D fingerprint plots were analysed for both molecules in order to understand the relationship between the crystal structures. The analysis shows that the lengths of the observed hydrogen bonds and other intermolecular interactions in (II) are relatively shorter than those observed in (I). Further, the analysis demonstrates the predominant participation of the sulfonyl-O atom and the carbonyl-O atom as the hydrogen bond acceptors in (I) and (II), respectively.
 
C13H15NO2S3, triclinic, P1 (no. 2), a = 7.2618(5) Å, b = 8.3190(6) Å, c = 13.2073(10) Å, a = 93.117(2)°, b = 97.485(2)°, g = 109.523(2)°, V = 741.5 Å3, Z = 2, Rgt(F) = 0.0573, wRref(F2) = 0.1646, T = 150 K.
 
C19H16BrCl2N5O, triclinic, P1̅ (no. 2), a = 7.4661(3) Å, b = 10.9874(4) Å, c = 12.8619(5) Å, ɑ = 109.979(3)°, β = 92.053(3)°, γ = 95.677(3)°, V = 984.0 ų, Z = 2, Rgt(F) = 0.0653, wRref(F²) = 0.1906, T = 296 K.
 
Visualisation of a model of Na-SAPO-34 used in the calcula- tions. One complete chabazite cage as well as the surrounding d6R units are included in the figure. The unit cell is highlighted with blue lines. Colour code: Dark purple =  sodium, grey =  aluminium, light purple =  phosphorus, yellow =  silicon, red =  oxygen. Figure prepared using Vesta [50] (For the colour version of this figure, the reader is referred to the electronic version of this article). 
Equilibrium distances between cation and guest molecule obtained from DFT-D calculations. Squares =  methane, triangles pointing down =  carbon monoxide, triangles pointing up =  nitrogen. Circles correspond to the ionic radii [63]. 
Isosurfaces of the electron density difference for methane adsorbed in Li-, Mg-, Cu/Na-, and Fe-SAPO-34. Blue areas corre- spond to an accumulation of electron density, whereas yellow areas correspond to a depletion of electron density. The isosurfaces were created for a density value of 0.01 e Å –3 (For the colour version of this figure, the reader is referred to the electronic version of this article). 
Isosurfaces of the electron density difference for CO adsorbed in Li-, Mg-, Cu/Na-, and Fe-SAPO-34. The colour scheme and the isodensity value are the same as in Figure 3 (For the colour version of this figure, the reader is referred to the electronic version of this article). 
Isosurface of the electron density difference for N 2 adsorbed in Li-, Mg-, Cu/Na-, and Fe-SAPO-34. The colour scheme and the isodensity value are the same as in Figure 3 (For the colour version of this figure, the reader is referred to the electronic version of this article). 
Density-functional theory calculations including a semi-empirical dispersion correction (DFT-D) are employed to study the interaction of small guest molecules (CH4, CO, N2) with the cation sites in the silicoaluminophosphate SAPO-34. Eight different cations from three different groups (alkali cations, alkaline earth cations, transition metals) are included in the study. For each case, the total interaction energy as well as the non-dispersive contribution to the interaction are analysed. Electron density difference plots are used to investigate the nature of this non-dispersive contribution in more detail. Despite a non-negligible contribution of polarisation interactions, the total interaction remains moderate in systems containing main group cations. In SAPOs exchanged with transition metals, orbital interactions between the cations and CO and N2 lead to a very strong interaction, which makes these systems attractive as adsorbents for the selective adsorption of these species. A critical comparison with experimental heats of adsorption shows reasonable quantitative agreement for CO and N2, but a pronounced overestimation of the interaction strength for methane. While this does not affect the conclusions regarding the suitability of TM-exchanged SAPO-34 materials for gas separations, more elaborate computational approaches may be needed to improve the quantitative accuracy for this guest molecule. Primary data can be downloaded from the NoMaD repository: http://dx.doi.org/10.17172/NOMAD/20150306181240
 
Density-functional theory (DFT) calculations are widely employed to study the interaction of water molecules with zeolite frameworks. However, there have been only few attempts to assess whether these computations reproduce experimental structure data sufficiently well, especially with regard to the hydrogen positions of the water molecules. In this work, a detailed comparison between experimental crystal structures and DFT-optimised structures is made for six water-loaded natural zeolites. For each system, high-quality structure determi-nations from neutron diffraction data have been reported (bikitaite/Li–BIK, edingtonite/Ba–EDI, gismondine/Ca– GIS, scolecite/Ca–NAT, natrolite/Na–NAT, yugawaralite/ Ca–YUG). Using a plane-wave DFT approach, the performance of six pure and three dispersion-corrected exchange-correlation functionals is compared, focusing on an optimisation of the atomic coordinates in a fixed unit cell (with cell parameters taken from experiment). It is found that the PBE and the PW91 functional give the smallest overall deviation between experiment and computation. Of the dispersion-corrected approaches, the PBE–TS functional exhibits the best performance. For the PBE and PBE–TS functionals, the agreement between experiment and DFT is analysed in more detail for different groups of interatomic distances. Regarding the OW–H distances in the water molecules, the DFT optimisations lead to physically realistic bond lengths. On the other hand, DFT has a systematic tendency to underestimate the length of hydrogen bonds. The cation-oxygen distances are mostly in very good agreement with experiment , although some exceptions indicate the necessity of further studies.
 
A new one-dimensional Zn(II)–cyanide complex with 1-methylimidazole ligand, [Zn(μ-CN)(CN)(1-meim)]n (1-meim: 1-methylimidazole) has been synthesized and characterized by spectral (FT-IR and Raman) methods, elemental analysis, thermal (TG, DTG and DTA) analysis and single crystal X-ray diffraction techniques. The complex crystallizes in the monoclinic system, P21 space group. The asymmetric unit contains one Zn(II), one 1-meim and two cyanide ligands. The coordination sphere of the Zn(II) ion exhibits a distorted tetrahedral geometry. In the crystal structure, the symmetry related zinc(II) atoms are bridged by the cyanide anions to form one dimensional chains running along the b-axis. Intermolecular C–H···N hydrogen bonds link the adjacent polynuclear chains forming two dimensional layers through the R1818(2) ring motifs, where the layers formed are oriented in parallel to (020).
 
C9H9IO3, orthorhombic, Pnma (no. 62), a = 10.9655(5) Å, b = 6.5768(3) Å, c = 13.3770(6) Å, V = 964.7 Å3, Z = 4, Rgt(F) = 0.0130, wRref(F2) = 0.0350, T = 200 K.
 
Lead and copper(I) chloride arsenite was found in the ancient metallurgic slag from the Vrissaki area, Lavrion district, Attikí Peninsula, Greece. Its chemical composition corresponds to the idealized formula Pb6Cu+(AsO3)2Cl7. The IR spectrum shows the presence of AsO3−3 anions and only a trace amount of O–H bonds. The crystal structure was solved by direct methods and refined to R(F) = 0.0304 based on 1778 unique reflections with I > 2σ(I). The compound is trigonal (rhombohedral), R3̅, a = 9.8691(2), c = 34.2028(13) Å, V = 2885.01(14) Å3, Z = 6. Two crystallographically non-equivalent As3+ cations occupy apexes of the AsO3 pyramids. Cu+ cation occupies an apex of the CuCl3 pyramid. The group [Cl3Cu–AsO3] is arranged along the c axis. Pb cations occupy two sites with seven- and eight-fold coordination. The crystal-chemical formula of the compound is Pb6(Cu+Cl3)(As3+O3)2Cl4.
 
Cyanide- and fumarate-bridged bimetallic complex, poly[μ-fumaratotetraaminedizinc(II) di-μ-cyanodicyanonickel(II) dihydrate], {[Zn2(μ-fum) (NH3)4Ni(μ-CN)2(CN)2]·2H2O}n (1) (H2fum = Fumaric acid) was synthesized and structurally characterized by vibrational (FT-IR and Raman) spectroscopy, single crystal X-ray diffraction and elemental and thermal analyses techniques. The structure of the complex consists of a one-dimensional polymeric chain, in which the Zn(II) and Ni(II) ions are linked by CN groups. The Ni(II) ion is four coordinated with four cyanide-carbon atoms in a square planar arrangement and the Zn(II) ions are four coordinated with one cyanide nitrogen atom, two amine nitrogen atoms and one fumarate oxygen atom, in a distorted tetrahedral arrangement. In the complex, the adjacent chains are connected by strong O–H···O, O–H···N, N–H···O and N–H···N hydrogen bonding interactions to form a three dimensional network.
 
Cyanide- and fumarate-bridged bimetallic complex, poly[μ-fumaratotetraaminedizinc(II) di-μ-cyanodicyanonickel(II) dihydrate], {[Zn2(μ-fum) (NH3)4Ni(μ-CN)2(CN)2]·2H2O}n (1) (H2fum = Fumaric acid) was synthesized and structurally characterized by vibrational (FT-IR and Raman) spectroscopy, single crystal X-ray diffraction and elemental and thermal analyses techniques. The structure of the complex consists of a one-dimensional polymeric chain, in which the Zn(II) and Ni(II) ions are linked by CN groups. The Ni(II) ion is four coordinated with four cyanide-carbon atoms in a square planar arrangement and the Zn(II) ions are four coordinated with one cyanide nitrogen atom, two amine nitrogen atoms and one fumarate oxygen atom, in a distorted tetrahedral arrangement. In the complex, the adjacent chains are connected by strong O–H···O, O–H···N, N–H···O and N–H···N hydrogen bonding interactions to form a three dimensional network.
 
Projection of a strongly folded single-chain parallel to [001]. For sake of clarity, three translationally equivalent tetrahedra have been marked with a " star " symbol. 
Side view of the whole crystal structure of Na 3 TmSi 3 O 9. Larger light and smaller medium grey spheres correspond to the sodium and oxygen atoms, respectively. 
Temperature dependence of the components α 11 (triangles), α 22 (circles) and α 33 (rhombs) of the thermal expansion tensor of Na 3 TmSi 3 O 9 . 
Evolution of the 12 symmetry independent Si-O-Si angles as a function of temperature. 
{4,4,15}-PME's for the T (Si) nodes in Na 3 Tm[Si 3 O 9 ] drawn in a polyhedral representation. 
Single-crystals of Na3TmSi3O9 were obtained in the course of systematic studies on the synthesis of rare earth element containing silicates from alkali fluoride flux systems. At 25 degrees C, the compound has the following basic crystallographic data: space group P2(1)2(1)2(1), a = 15.1681(3) angstrom, b = 15.0855(3) angstrom, c = 14.9937(3) angstrom, V = 3430.83(12) angstrom(3), Z = 16. Structure solution was based on direct methods. The subsequent refinement calculations resulted in a residual of R(|F|) = 0.039 for 9159 independent observed reflections with I > 2 sigma(I) and 579 parameters. From a structural point of view, Na3TmSi3O9 belongs to the group of single-chain silicates. The periodicity of the extremely folded chains has a value of 24. The compound is isostructural with the corresponding yttrium phase. Alternatively, the structure can be described as a mixed octahedral-tetrahedral framework, for which a detailed topological analysis is presented. Furthermore, a distinct pseudo-symmetry was observed. The sub-structure of the silicon and thulium atoms fulfills the symmetry requirements of P4(1)2(1)2 within a few tenths of an angstrom ngstrom. The high-temperature behavior of Na3TmSi3O9 was investigated by in-situ single-crystal X-ray diffraction in the range between 25 and 700 degrees C. No anomalies in the lattice parameters and unit cell volume vs. temperature curves were observed, pointing to the absence of structural phase transitions. From the evolution of the lattice parameters, the thermal expansion tensor alpha(ij) has been determined. Thermal expansion shows a pronounced anisotropy. In the whole temperature region, the largest values are observed along [010] (parallel to the single-chains).
 
In a comparative structural study, the solid state structures within the homologous series of alkane-α,ω-diphosphonic acids, H2O3P–(CH2)n–PO3H2 with n = 6–12, have been characterised by powder and single crystal X-ray diffraction. The crystal structures of the odd-numbered diphosphonic acids were found to be homotypic. For the even-numbered diphosphonic acids – including the two already known polymorphs of butane-1,4-diphosphonic acid – two different types are found. Basically, all alkane-α,ω-diphosphonic acids exhibit pillared-layered structures with their terminal groups forming two-dimensional hydrogen bonded networks which are covalently bridged by alkylene chains. Structural differences occur within the hydrogen bonding systems as well as in the arrangement of the alkylene chains. Based on the existence of different structure types of the alkane-α,ω-diphosphonic acids, the progression of their melting points can be explained.
 
The dinuclear complex tris(2-aminoethyl) aminezinc(II)- μ -cyanothreecyanozincate(II) hemihydrate, [Zn(tren)Zn( μ -CN)(CN) 3 ] · 0.5H 2 O ( 1 ) (tren = tris(2-aminoethyl) amine), has been synthesized and characterized by spectral (FT-IR and Raman), elemental, thermal analysis (TG, DTG and DTA) as well as single crystal X-ray diffraction techniques. The asymmetric unit is composed of two Zn(II) ions, one tren ligand, four cyanide ligands and a half crystal water molecule which is situated at the special position. Zn1 ion exhibits tetrahedral coordination geometry with four carbon atoms of four cyanide ligands. Zn2 ion is five-coordinated by five nitrogen atoms from one tren and one cyanide ligands in a trigonal bipyramid coordination geometry. The cyanide nitrogen is in the axial position. Adjacent dinuclear units are connected by hydrogen bonding interactions to form three dimensional network. The decomposition reaction takes place in the temperature range 30 – 700 ° C in the static air atmosphere.
 
Tensorial properties such as thermal expansion, optical rotation, the electro-optic effect, elastic constants, and many more are prepared with a Windows executable, WinTensor, for rendering a graphical representation that can be viewed on a monitor or printed out for a tangible 3D model. Examples of 3D printed representation surfaces in KH
 
A new one-dimensional Zn(II)–cyanide complex with 1-methylimidazole ligand, [Zn( μ -CN)(CN)(1-meim)] n (1-meim: 1-methylimidazole) has been synthesized and characterized by spectral (FT-IR and Raman) methods, elemental analysis, thermal (TG, DTG and DTA) analysis and single crystal X-ray diffraction techniques. The complex crystallizes in the monoclinic system, P2 1 space group. The asymmetric unit contains one Zn(II), one 1-meim and two cyanide ligands. The coordination sphere of the Zn(II) ion exhibits a distorted tetrahedral geometry. In the crystal structure, the symmetry related zinc(II) atoms is bridged by the cyanide anions to form one dimensional chains running along the b-axis. Intermolecular C–H · · · N hydrogen bonds link the adjacent polynuclear chains forming two dimensional layers through the 18 R18 ( 2) ring motifs, where the layers formed are oriented in parallel to (020).
 
A new one-dimensional Zn(II)–cyanide complex with 1-methylimidazole ligand, [Zn( μ -CN)(CN)(1-meim)] n (1-meim: 1-methylimidazole) has been synthesized and characterized by spectral (FT-IR and Raman) methods, elemental analysis, thermal (TG, DTG and DTA) analysis and single crystal X-ray diffraction techniques. The complex crystallizes in the monoclinic system, P2 1 space group. The asymmetric unit contains one Zn(II), one 1-meim and two cyanide ligands. The coordination sphere of the Zn(II) ion exhibits a distorted tetrahedral geometry. In the crystal structure, the symmetry related zinc(II) atoms is bridged by the cyanide anions to form one dimensional chains running along the b-axis. Intermolecular C–H · · · N hydrogen bonds link the adjacent polynuclear chains forming two dimensional layers through the 18 R18 ( 2) ring motifs, where the layers formed are oriented in parallel to (020).
 
Crystal packing of (I). Hydrogen bonds are shown as dotted lines. 
The crystal structures of two closely related compounds, namely, N-(4-fluorobenzoyl)-benzenesul-fonamide (I) and N-(4-fluorobenzoyl)-4-methylbenze-nesulfonamide (II) are investigated by analysing the packing patterns and intermolecular interactions, and also by Hirshfeld surface analysis. The crystal structure of each of (I) and (II) displays a two-dimensional architecture. Hirshfeld surfaces comprising d norm surface and 2D fingerprint plots were analysed for both molecules in order to understand the relationship between the crystal structures. The analysis shows that the lengths of the observed hydrogen bonds and other intermolecular interactions in (II) are relatively shorter than those observed in (I). Further, the analysis demonstrates the predominant participation of the sulfonyl-O atom and the carbonyl-O atom as the hydrogen bond acceptors in (I) and (II), respectively.
 
C24H32O4, orthorhombic, P2(1)2(1)2(1) (no, 19), a = 7.0809(3) angstrom, b = I 5.0684(6) angstrom, c = 20.6315(10) angstrom, V= 2201.3 angstrom(3), Z = 4, R-gt(F) = 0,0304, wR(ref)(F-2) = 0,0753, T = 173 K.
 
C24H32O4, orthorhombic, P212121 (no. 19), a = 7.0809(3) Å, b = 15.0684(6) Å, c = 20.6315(10) Å, V = 2201.3 Å3, Z = 4, Rgt(F) = 0.0304, wRref(F2) = 0.0753, T = 173 K.
 
( Color online ). ab projection of the β -Ca 3 (PO 4 ) 7 structure (a). Columns A and B are indicated and the layer I the with B columns (b) and the layer II with the columns A and B (c) are shown. M4 site is half-occupied. 
( Color online ). The environment of the octahedral M 5 site in the Ca 9 (Fe 0.63 Mg 0.37 )H 0.37 (PO 4 ) 7 structure. 
( Color online ). a) Part of the A column in the Ca 9 (Fe 0.63 Mg 0.37 ) H 0.37 (PO 4 ) 7 structure. Dashed lines shows oxygen atoms connected with hydrogen. b) The environment of P1O 4 tetrahedra with P3O 4 tetrahedra and probable location of H + between O1 and O10 with for- mation of O1H-bonds and hydrogen bonds H···O10 in the structure. 
A new hydrogen-containing whitlockite-type phosphate Ca 9 (Fe 0.63 Mg 0.37)H 0.37 (PO 4) 7 : hydrothermal synthesis and structure Abstract: A new hydrogen-containing Ca 9 (Fe 0.63 Mg 0.37) H 0.37 (PO 4) 7 phosphate with the whitlockite-type structure has been synthesized by a hydrothermal method and its structure has been studied by the single-crystal X-ray dif-fraction. The compound crystallizes in the trigonal space group R3c (traditional for compounds with the whitlockite-type structure) with unit-cell parameters: a = 10.3533(1) Å, c = 37.1097(4) Å. The structure has been determined using the "charge flipping" method. Ca 9 (Fe 0.63 Mg 0.37)H 0.37 (PO 4) 7 structure is similar to that of other members of the whit-lockite-type family. The presence of hydrogen in the struc-ture leads to the formation of OH-group with one of the oxygen of PO 4 -tetrahedra. Based on an analysis of the bond valence sums (BVS) a conclusion has been made about localization of H atoms in the structure. Smaller values of BVS for O1 and O10 atoms than ones for other oxygen atoms indicate localization of H atoms between them in a position with site symmetry 18b.
 
C12H9N3O2, monoclinic, P21/c (no. 14), a = 7.524(1) Å, b = 7.981(1) Å, c = 17.622(2) Å, b = 98.31(1)°, V = 1047.0 Å3, Z = 4, Rgt(F) = 0.0581, wRref(F2) = 0.1337, T = 293 K.
 
C8H18N2, monoclinic, P21/n (no. 14), a = 9.708(9) Å, b = 14.988(17) Å, c = 13.207(12) Å, " = 95.92(3)°, V = 1911.4 Å3, Z = 8, Rgt(F) = 0.0369, wRref(F2) = 0.0937, T = 100 K.
 
Top-cited authors
Philip James Hasnip
  • The University of York
Matt Probert
  • The University of York
Matthew Segall
  • Optibrium Limited
X. Gonze
  • Université Catholique de Louvain - UCLouvain
Peter Paufler
  • Technische Universität Dresden