The Crystal Structure of the Pyrimidine Analogue Calcium 5-Ethylidenehydroorotate · 1.5 Hydrate, a Photoproduct of Ethylorotate

1976 ◽  
Vol 31 (9-10) ◽  
pp. 518-523 ◽  
Author(s):  
B Hingerty ◽  
E Kulikowska ◽  
W Saenger ◽  
D Shugar
Keyword(s):  
Crystal Structure ◽  
Calcium Salt ◽  
Direct Methods ◽  
Water Molecules ◽  
Monoclinic Space Group ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Photochemical Rearrangement ◽  
Pyrimidine Analogue

Abstract X-ray diffraction methods have been employed to establish the crystal structure of a new, unusual pyrimidine analogue, 5-ethylidenehydroorotate, obtained by a photochemical rearrangement of 5-ethylorotate. Crystals of the calcium salt of the title compound are monoclinic, space group Pc, cell constants a=14.631, 6 = 10.038, c = 19.168 Å,β = 137.7°, and contain four molecules, two cations and three water molecules per asymmetric unit. The structure was solved by direct methods and refined to R = 5.2% on the basis of 2653 diffractometer measured data. The four independent molecules represent two pairs of enantiomers with slightly differing conformations linked together by an intricate system of hydrogen bonding and Ca2+-coordination (pentagonal bipyrimidal). The structure of the compound in aqueous medium, as that in the crystal.

The halotrichite group: the crystal structure of apjohnite

1976 ◽  
Vol 40 (314) ◽  
pp. 599-608 ◽  
Author(s):  
S. Menchetti ◽  
C. Sabelli
Keyword(s):  
Crystal Structure ◽  
Least Squares Method ◽  
Direct Methods ◽  
Water Molecules ◽  
Monoclinic Space Group ◽  
Direct Connection ◽  
Asymmetric Unit ◽  
X Ray ◽  
Bonding System ◽  
Hydrogen Bonding System

SummaryApjohnite, MnAl2(SO4)4·22H2O, is monoclinic, space group P21/c, a 6·198 (2), b 24·347 (4), c 21·266 (4) Å, β 100·28 (3)° and Z = 4. The crystal structure was determined by means of direct methods applied to X-ray data collected with a single-crystal diffractometer. At the end of the refinement, performed with least-squares method, the R index was 0·039.The SO4 tetrahedra, Al(H2O)5 octahedra, and MnO(H2O)5 octahedra are connected by a hydrogen bonding system; the only direct connection between polyhedra is by sharing of an oxygen between S(4) and Mn. In the asymmetric unit there are twenty-two water molecules, five of which lie in channels of the structure and are not linked to the cations but only to ligand water oxygens by means of hydrogen bonds.Powder data indicate a close structural relationship between apjohnite, halotrichite, and pickeringite.

Crystal structure of cis-Tetracarbonylbis(chloromercury)iron

1976 ◽  
Vol 29 (9) ◽  
pp. 1905 ◽  
Author(s):  
CL Raston ◽  
AH White ◽  
SB Wild
Keyword(s):  
Crystal Structure ◽  
Least Squares ◽  
Diffraction Data ◽  
Title Compound ◽  
Direct Methods ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Independent Molecules

The crystal structure of the title compound has been determined by direct methods from X-ray diffraction data and refined by least squares to a residual of 0.071 for 2647 'observed' reflections. Crystals are monoclinic, C2/c, a = 36.81(1), b = 11.181(2), c = 20.369(5) �, β = 95.28(3)�, Z = 32. There are four independent molecules in the asymmetric unit, all with the cis disposition of ligands (<Fe-Hg), 2.498 �; <Hg-Fe-Hg), 80.9�); in one of the molecules one of the carbonyl sites is occupied by a more substantial moiety, possibly a result of partial occupancy of HgCl as a result of disorder or decomposition.

scholarly journals The reaction of 3,5-diphenyl-1,2-dithiolium-4-olate with aniline: the crystal structure of 1-phenylimino-2-phenylamino-3-phenylindene

1987 ◽  
Vol 65 (12) ◽  
pp. 2830-2833 ◽  
Author(s):  
David M. McKinnon ◽  
Peter D. Clark ◽  
Robert O. Martin ◽  
Louis T. J. Delbaere ◽  
J. Wilson Quail
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Single Crystal ◽  
Least Squares ◽  
Direct Methods ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cell Dimensions ◽  
Unit Cell Dimensions

3,5-Diphenyl-1,2-dithiolium-4-olate (1) reacts with aniline to form 1-phenylimino-2-phenylamino-3-phenylindene (3a). Under suitable conditions, 6-phenylbenzo[b]indeno[1,2-e]-1,2-thiazine is also formed. These structures are confirmed by alternative syntheses. The molecular structure of 3a has been determined by single crystal X-ray diffraction. Compound 3a crystallizes in the monoclinic space group C2/c with unit cell dimensions a = 20.777(3) Å, b = 6.130(3) Å, c = 31.327(3) Å, 3 = 99.59(1)°, and Z = 8. The structure was solved by direct methods and refined by least squares to a final R = 0.055. The molecular structure of 3a shows the three phenyl containing substituents to have the planes of their ring systems tilted between 40° and 60° from the plane of the indene system due to steric repulsions.

Odigitriaite, CsNa5Ca5[Si14B2O38]F2, a new caesium borosilicate mineral from the Darai-Pioz alkaline massif, Tajikistan: Description and crystal structure

2017 ◽  
Vol 81 (1) ◽  
pp. 113-122 ◽  
Author(s):  
Atali A. Agakhanov ◽  
Leonid A. Pautov ◽  
Elena Sokolova ◽  
Frank C. Hawthorne ◽  
Vladimir Yu Karpenko ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Double Layer ◽  
Direct Methods ◽  
Double Layers ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Calculated Density ◽  
X Ray ◽  
Mohs Hardness ◽  
Alkaline Massif

AbstractOdigitriaite, a new Cs, Na, Ca borosilicate mineral, was discovered in moraine adjacent to the Darai-Pioz alkaline massif in the upper reaches of the Darai-Pioz river at the intersection of the Turkestansky, Zeravshansky and Alaisky mountain ridges, Tajikistan. It occurs as irregular thin flakes associated with quartz, pectolite, baratovite, fluorite, pekovite, polylithionite, aegirine, leucosphenite, pyrochlore, neptunite, reedmergnerite, mendeleevite-(Ce), zeravshanite and sokolovaite. It is colourless with a white streak, is translucent and has a vitreous lustre; it does not fluoresce under ultraviolet light. Odigitriaite is brittle with an uneven fracture and a Mohs hardness of 5. The calculated density is 2.80(2) g/cm3. The indices of refraction are α = 1.502, β = 1.564, γ = 1.576; 2Vobs = 46(2)°, dispersion is weak r > v, and there is no pleochroism. The chemical composition is as follows (electron microprobe, H2O calculated from structure): SiO2 55.30, Al2O3 0.09, Y2O3 0.44, MnO 0.94, FeO 0.10, PbO 0.21, K2O 0.01 Cs2O 8.36, B2O3 4.75, H2O 0.37, F 1.74, O = F2 –0.74, total 99.43 wt.%. The empirical formula of odigitriaite is Cs0.90Na5.12Ca4.68Mn0.20Y0.06Fe0.02Pb0.01[Si13.92Al0.03B2.06O38]F1.39(OH)0.62. The end-member formula is CsNa5Ca5[Si14B2O38]F2. The strong reflections in the powder X-ray diffraction pattern are: [(d, Å), (I, %), (hkl)]: 5.45 (25) (1 1 3), 4.66 (33) (3 1 1), 4.40 (26) (0 2 2), 4.10 (36) (3 1 3), 3.95 (25) (3̄ 1 3), 2.85 (31) (2 2 2), 2.68 (40) (0 0 6), 3.62 (45) (0 2 4), 3.35 (100) (2̄ 2 4), 3.31 (30) (3̄ 1 5), 3.25 (35) (4 0 4), 3.04 (60) (4̄ 2 2), 2.925 (22) (4̄ 2 3), 1.813 (23) (9 1 0). Odigitriaite is monoclinic, space group C2/c, a = 16.652(5), b = 9.598 (3), c = 22.120(7) Å, β= 92.875(14)°, V = 3530.9(1.9) Å3, Z = 4. The crystal structure of odigitriaite was solved by direct methods and refined to an R1 value of 2.75% based on single-crystal X-ray data. It is a double-layer sheet-borosilicate mineral; Cs and Na are intercalated within the double-layer sheet, and the double layers are linked by interstitial Ca and Na atoms.

scholarly journals A New 3D Coordination Polymer of Bismuth with Nicotinic AcidN-Oxide

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Farzin Marandi ◽  
Ingo Pantenburg ◽  
Gerd Meyer
Keyword(s):  
Crystal Structure ◽  
Thermal Stability ◽  
Coordination Polymer ◽  
Three Dimensional ◽  
Water Molecules ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Thermal Stability Of

The new three-dimensional coordination polymer {[Bi(NNO)2(NO3)]·1.5H2O}n(1, NNO−= nicotinateN-oxide) was synthesized and characterized by elemental analysis, IR and1H-NMR spectroscopy, as well as single-crystal X-ray diffraction analysis.1crystallizes in the monoclinic space group C2/c. The crystal structure consists of a rectangular-shaped grid constructed with NNO linkers. Cavities of a diameter of 7.9–8.3 Å2are filled with disordered water molecules. The thermal stability of the compound was evaluated by thermogravimetric analysis.

Supercell and subcell description of the crystal structure of triammonium bis(O-phospho-L-serinate) trihydrate

2006 ◽  
Vol 62 (5) ◽  
pp. 919-925 ◽  
Author(s):  
Małgorzata Hołyńska ◽  
Iwona Bryndal ◽  
Tadeusz Lis
Keyword(s):  
Crystal Structure ◽  
Diffraction Pattern ◽  
Water Molecules ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Data Set ◽  
Space Group ◽  
X Ray ◽  
Average Structure ◽  
Structure Solution

The X-ray diffraction pattern obtained for a crystal of triammonium bis(O-phospho-L-serinate) trihydrate at 100 K displays the presence of weak superstructure reflections with odd l indices. Omission of the superstructure reflections leads to orthorhombic Laue symmetry. The structure may be solved and refined in the space group P212121 as an average structure omitting the weak reflections. The model reveals the presence of O-phospho-L-serinate monoanions, ammonium cations and partly disordered water molecules. The structure solution for the whole data set could be obtained only in the space group P21. There are two monoanions and two dianions of O-phospho-L-serinate per asymmetric unit, as well as six ordered ammonium cations and six water molecules.

Crystal structure of tert-butyl-6-methyl 8,9-(1,2-[60]fullereno) tricyclo[3.2.2.02,4] non-6-ene-carboxylate with CHCl3 and hexane solvent at 120 K

1999 ◽  
Vol 214 (7) ◽  
Author(s):  
D. Zobel ◽  
M. Strümpel ◽  
P. Luger ◽  
M. Ramm ◽  
W. Duczek ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Title Compound ◽  
Direct Methods ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Tert Butyl

AbstractThe crystal structure of the title compound was determined by X-ray diffraction at 120 K and solved by direct methods. The asymmetric unit of the

Crystal structure of 9-Oxofluorene-4-carboxylic acid

1981 ◽  
Vol 34 (5) ◽  
pp. 1143 ◽  
Author(s):  
CHL Kennard ◽  
G Smith ◽  
GF Katekar
Keyword(s):  
Crystal Structure ◽  
Carboxylic Acid ◽  
Diffraction Data ◽  
Three Dimensional ◽  
Direct Methods ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
A Cell

The crystal structure of 9-oxofluorene-4-carboxylic acid has been determined by direct methods using three-dimensional X-ray diffraction data, and refined to R0·068 for 1323 'observed' reflections. Crystals are monoclinic, space group P21/c with 24 in a cell of dimensions a 3·843(3), b 7·986(5), c 3269(2) �, β 96·64(4)�. The molecules form centrosymmetric hydrogen-bonded cyclic dimers [O···O 2·642(3) �] with the plane of the carboxylic acid making an angle of 26·5� with that of the 9-oxofluorene group. Stacks of molecules form down the a axis with 3.843 �. separation.

Molecular and Crystal Structure, and EPR Studies of Tetraphenylarsonium [Bis-(1,3-dithia-2-one-4,5-dithiolato)-nickelate], (AsPh4)[Ni(dmid)2]

1988 ◽  
Vol 43 (9) ◽  
pp. 1137-1143 ◽  
Author(s):  
R. Vicente ◽  
J. Ribas ◽  
C. Zanchini ◽  
D. Gatteschi ◽  
J.-P. Legros ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Dihedral Angle ◽  
Unpaired Electron ◽  
Room Temperature ◽  
Monoclinic Space Group ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Variable Parameters ◽  
X Ray

AbstractThe crystal structure of (AsPh4)[Ni(dmid)2 (dmid2- = 1,3-dithia-2-one-4,5-dithiolato) has been determined by X-ray diffraction studies: crystals are monoclinic, space group P21/n a = 14.724(2), b = 14.305(5), c = 15.570(3) Å, β = 92.20(1)°, V = 3277 Å3 , ᵨx = 1.63 g cm-3 for Z = 4, final conventional agreement indices R = 0.038 and Rw = 0.049 for 2115 unique, observed reflections and 211 variable parameters. The asymmetric unit contains one (AsPh4)+ cation and one [Ni(dmid)2] anion, both in general positions. The anions are isolated from each other by the bulky cations. The [Ni(dmid)2]- ion deviates strongly from planarity: the dihedral angle between the two Ni(dmid) moieties is 10.7°; one of the dmid ligand is almost planar, while the second one is severely puckered. Polycristalline powder and single crystal EPR spectra have been recorded at room temperature. Only one signal was observed in all crystal orientations. The angular depend-ences of the linewidth and of the g values have been determined, as well as the principal g values and directions. These results have been compared to those previously obtained for the analogue (n-Bu4N)[Ni(dmit)2 ] (drnit2- = 1,3-dithia-2-thione-4,5-dithiolato), and discussed in terms of the localization of the unpaired electron on the ligands. leading to a formal (III) and actual (II) nickel oxidation state.

scholarly journals Synthesis and Structural Characterization of ‘Non-VSEPR’ Structures of Oxo-Tungsten Complex

2011 ◽  
Vol 8 (s1) ◽  
pp. S323-S329
Author(s):  
Shahriare Ghammamy ◽  
Hajar Sahebalzamani
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Structural Characterization ◽  
Direct Methods ◽  
Donor Ligands ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cis And Trans

The crystal structure of [(CH3)4N]4[WOCl4F][WO3Cl4] was determined by single crystal x-ray diffraction technique. The crystal is monoclinic, space group C 2/m, with a= 28.23(10) Å, b= 11.60(4) Å,c= 13.48(5) Å, β=118.43(7)°, V= 3886(2)Å3, Z=4. The structure was solved by direct methods and refined by least-squares methods to a final R = 0.0512 for 3825 observed reflections with I>2σ(I). In crystal there are two crystallographic distinct anions, both with cis geometry; the O-W-F and O-W-O angles are 97.5(3)° and 103.1(3) ° respectively. All structures are cis configurations that confirm a preference for angles below 90° and 180° between cis and trans σ-donor ligands, respectively.

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