Erratum to: Tautomerism in acyl-pyrazolones and in a novel photolysis product—importance and impact of the accurate localization of hydrogen atoms in crystal structures

The Patterson superposition methods described by Burlaet al.[J. Appl. Cryst.(2006),39, 527–535], based on the use of the `multiple implication functions', have been enriched by supplementary filtering techniques based on some general (resolution-dependent) features of both the Patterson and the electron density maps. The method has been implemented in a modified version of the programSIR2004and tested using a set of 20 crystal structures selected from the Protein Data Bank, having a number of non-hydrogen atoms in the asymmetric unit larger than 2000, atomic resolution data and some heavy atoms (equal to or heavier than Ca). The new phasing procedure is able to solve most of the test structures, among which there are two proteins with more than 6000 non-hydrogen atoms in the asymmetric unit, so extending by far the complexity today commonly considered as the limit for Patterson-based methods (i.e.about 2000 non-hydrogen atoms).

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Structural and Spectral Studies of 2-Pyridineformamide Thiosemicarbazone and its Complexes Prepared with Zinc Halides

Zeitschrift für Naturforschung B ◽

10.1515/znb-2000-0612 ◽

2000 ◽

Vol 55 (6) ◽

pp. 511-518 ◽

Cited By ~ 32

Author(s):

Alfonso Castiñeiras ◽

Isabel Garcia ◽

Elena Bermejo ◽

Douglas X. West

Keyword(s):

Crystal Structure ◽

Crystal Structures ◽

Intermolecular Interactions ◽

Trigonal Bipyramid ◽

Spectral Studies ◽

Hydrogen Atoms ◽

Pyridyl Nitrogen ◽

Imine Nitrogen

Reduction of 2-cyanopyridine by sodium in dry methanol in presence of thiosemicarbazide produces 2-pyridineformamide thiosemicarbazone, HAm4DH. The crystal structure of HAm4DH, which has a number of intermolecular interactions involving its five NH hydrogen atoms, has been solved. Crystal structures of the complexes prepared by reaction of HAm4DH with zinc(II) chloride, bromide and iodide have also been obtained. Neutral HAm4DH is coordinated via the pyridyl nitrogen, imine nitrogen and thione sulfur atoms, and each complex is five-coordinate with two halogen ligands. The structures of the three complexes are best described as square pyramidal with [Zn(HAm4DH)l2] having the largest distortion toward a trigonal bipyramid.

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Zur Struktur von Dihydroxonium Alkandisulfonaten / The Structure of Dihydroxonium Alkanedisulfonates

Zeitschrift für Naturforschung B ◽

10.1515/znb-1994-1104 ◽

1994 ◽

Vol 49 (11) ◽

pp. 1467-1472 ◽

Cited By ~ 4

Author(s):

Peter Sartori ◽

Ralf Jüschke ◽

Roland Boese ◽

Dieter Bläser

Keyword(s):

Single Crystal ◽

Crystal Structures ◽

Ionic Form ◽

X Ray Diffraction ◽

Hydrogen Atoms ◽

X Ray ◽

Oxonium Ions

AbstractThe crystal structures of methanedisulfonic acid-(1) and 1,2-ethandisulfonic acid-dihydrate (2) have been determined from single crystal X-ray diffraction at T = 145 K (for 1) and T = 125 K (for 2). It has been found, that both acids exist in an ionic form as dihydroxonium sulfonates, but differ in the geometry of the sulfonate groups and in the positions of the hydrogen atoms at the oxonium ions.

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Crystal structures and Hirshfeld surface analyses of (E)-N′-benzylidene-2-oxo-2H-chromene-3-carbohydrazide and the disordered hemi-DMSO solvate of (E)-2-oxo-N′-(3,4,5-trimethoxybenzylidene)-2H-chromene-3-carbohydrazide: lattice energy and intermolecular interaction energy calculations for the former

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s2056989019012015 ◽

2019 ◽

Vol 75 (10) ◽

pp. 1403-1410 ◽

Cited By ~ 1

Author(s):

Ligia R. Gomes ◽

John Nicolson Low ◽

James L. Wardell ◽

Camiola Capelini ◽

Vitoria R.F. Câmara ◽

...

Keyword(s):

Interaction Energy ◽

Crystal Structures ◽

Intermolecular Interaction ◽

Three Dimensional ◽

Lattice Energy ◽

Hirshfeld Surface ◽

Hydrogen Atoms ◽

Intermolecular Interaction Energy ◽

Energy Calculations ◽

Dimensional Array

The crystal structures of the disordered hemi-DMSO solvate of (E)-2-oxo-N′-(3,4,5-trimethoxybenzylidene)-2H-chromene-3-carbohydrazide, C20H18N2O6·0.5C2H6OS, and (E)-N′-benzylidene-2-oxo-2H-chromene-3-carbohydrazide, C17H12N2O3 (4: R = C6H5), are discussed. The non-hydrogen atoms in compound [4: R = (3,4,5-MeO)3C6H2)] exhibit a distinct curvature, while those in compound, (4: R = C6H5), are essential coplanar. In (4: R = C6H5), C—H...O and π–π intramolecular interactions combine to form a three-dimensional array. A three-dimensional array is also found for the hemi-DMSO solvate of [4: R = (3,4,5-MeO)3C6H2], in which the molecules of coumarin are linked by C—H...O and C—H...π interactions, and form tubes into which the DMSO molecules are cocooned. Hirshfeld surface analyses of both compounds are reported, as are the lattice energy and intermolecular interaction energy calculations of compound (4: R = C6H5).

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Monomeric and Dimeric Cobalt(III) Polyoxomolybdates: Crystal Structures and Cyclic Voltammetry of Na3 [H6CoMo6O24].8H2O and K6 [H4Co2Mo10O38].7H2O

Australian Journal of Chemistry ◽

10.1071/c97218 ◽

1998 ◽

Vol 51 (9) ◽

pp. 825 ◽

Cited By ~ 11

Author(s):

Annette L. Nolan ◽

Christine C. Allen ◽

Robert C. Burns ◽

Donald C. Craig ◽

Geoffrey A. Lawrance

Keyword(s):

Cyclic Voltammetry ◽

Crystal Structures ◽

Electrochemical Behaviour ◽

Monoclinic Space Group ◽

X Ray Diffraction ◽

Hydrogen Atoms ◽

Space Group ◽

Ph Values ◽

Initial Reduction ◽

Common Plane

The crystal structures of Na3 [H6CoMo6O24].8H2O and K6 [H4Co2Mo10O38].7H2O have been determined by X-ray diffraction. The monomer, Na3 [H6CoMo6O24].8H2O, is triclinic, space group P-1, a 6·451(1), b 10·866(2), c 10·922(2) Å, α 109·20(1), β 106·90(1), γ 95·43(1)°, V 676·3(2) Å3, Z 1, and the structure was solved to an R1 value of 0·0243 (wR2 0·0784) for 3761 independent observed reflections. The anion exhibits the well known Anderson structure with six octahedral MoO6 edge-sharing units surrounding the central ‘CoO6’ octahedron, with all metals in a common plane. The dimer, K6 [H4Co2Mo10O38].7H2O, is monoclinic, space group P21/c, a 11·795(5), b 11·626(2), c 29·731(13) Å, β 95·33(2)°, V 4059(3) Å3, Z 4, and the structure was solved to an R1 value of 0·0215 (wR2 0·1040) for 6546 independent observed reflections. The anion can be derived from the monomeric hexamolybdocobaltate(III) ion by removing one ‘MoO5’ unit (ignoring the hydrogen atoms) from each of two monomer anions, turning one 180° around a CoO6 octahedral diagonal, and joining them to create two CoO6 octahedra sharing an edge. Cyclic voltammetry shows that both anions are irreversibly reduced at low pH values (4·0–4·5), likely as a result of chemical reactions following the initial reduction steps. At higher pH values (4·5–5·4), a change in speciation occurs in both cases, most likely the result of the formation of less highly protonated species, which also display irreversible electrochemical behaviour.

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ChemInform Abstract: BRIDGING OF THORIUM BY HYDROGEN ATOMS OF METHYLTRIHYDROBORATE GROUPS. CRYSTAL STRUCTURES OF BIS(TETRAKIS(METHYLTRIHYDROBORATO)THORIUM(IV)) ETHERATE AND BIS(TETRAKIS(METHYLTRIHYDROBORATO)THORIUM(IV) TETRAHYDROFURANATE)

Chemischer Informationsdienst ◽

10.1002/chin.198551254 ◽

1985 ◽

Vol 16 (51) ◽

Author(s):

R. SHINOMOTO ◽

J. G. BRENNAN ◽

N. M. EDELSTEIN ◽

A. ZALKIN

Keyword(s):

Crystal Structures ◽

Hydrogen Atoms

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Chemistry and crystal structures of tetrabenzoylethylene, its photolysis product and tetraacetylethylene

Australian Journal of Chemistry ◽

10.1071/ch9781265 ◽

1978 ◽

Vol 31 (6) ◽

pp. 1265 ◽

Cited By ~ 11

Author(s):

JR Cannon ◽

VA Patrick ◽

CL Raston ◽

AH White

Keyword(s):

Solid State ◽

Crystal Structures ◽

Molecular Conformation ◽

Crystallographic Analysis ◽

Stable Form ◽

Photolysis Product ◽

Molecular Conformations ◽

X Ray ◽

The Difference ◽

The Stability

X-ray crystallographic analysis has revealed that the light-sensitive form (A) and the light-stable form (A') of tetrabenzoylethylene are not valence tautomers but are two crystalline modifications of the same substance. The difference in the stability of these forms to light appears to be a consequence of their different molecular conformations and packing in the solid state. The molecular conformation of the A form is represented by (8) and that of the A' form by (9). The related tetraacetylethylene has the conformation (10) in the solid state. X-ray crystallographic analysis has also revealed that the photolysis product (B) of tetrabenzoylethylene is 4-phenoxy-3,4,6-triphenyl-1H,4H-furo[3,4-c]-furan-1-one (11). �� The crystal structures of (8), (9), (10) and (11) were determined by X-ray diffraction: diffractometer data at 295 K were refined by least-squares techniques to residuals of 0.064 (2161 'observed' reflections) for (8), 0.057 (1310) for (9), 0.049 (1295) for (10) and 0.061 (1639) for (11). Crystals of (8) are monoclinic, P21/n, a 8.775(5), b 17.352(9), c 30.985(8)Ǻ, β 93.01(3)°, Z 8. Crystals of (9) which contain carbon disulfide are monoclinic, A2/a, a 21.21(2), b 6.181(4), c 20.35(2) Ǻ, β 102.77(7)°, Z 4. Crystals of (10) are monoclinic, P21/n, a 7.540(2), b 4.392(2), c 14.770(4) Ǻ, β 96.29(2)°, Z 2. Crystals of (11) are monoclinic, P1/n, a 14.820(4), b 15.000(3), c 10.819(4)Ǻ, β 106.02(2)°, Z 4.

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Two crystal structures of 10,10′-(l,4-phenylene-dimethylidene)-bis-9,10-H-anthracenone

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1524/zkri.1992.200.3-4.247 ◽

1992 ◽

Vol 200 (3-4) ◽

Author(s):

G. Dewald ◽

M. Hanack ◽

E.-M. Peters ◽

L. Walz

Keyword(s):

Crystal Structures ◽

Diffraction Data ◽

Molecular Structures ◽

Monoclinic Space Group ◽

X Ray Diffraction ◽

Hydrogen Atoms ◽

Space Group ◽

X Ray ◽

Crystal And Molecular Structures

AbstractThe crystal and molecular structures of dimorphic 10,10′-(1,4-phenylene-dimethylidene)-bis-9,10-H-anthracenone (1) have been determined using X-ray diffraction data. The compound crystallizes either in the monoclinic space groupSince all non-hydrogen atoms are of pure

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Syntheses and crystal structures of 2-(p-tolyl)-1H-perimidine hemihydrate and 1-methyl-2-(p-tolyl)-1H-perimidine

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s2056989022000287 ◽

2022 ◽

Vol 78 (2) ◽

Author(s):

Paulina Kalle ◽

Sergei V. Tatarin ◽

Marina A. Kiseleva ◽

Alexander Yu. Zakharov ◽

Daniil E. Smirnov ◽

...

Keyword(s):

Water Molecule ◽

Crystal Structures ◽

Crystal Packing ◽

Rotation Axis ◽

Point Group ◽

Group Symmetry ◽

X Ray Diffraction ◽

Hydrogen Atoms ◽

H Nmr ◽

Rotation Axes

The title compounds, 2-(4-methylphenyl)-1H-perimidine hemihydrate (1, C18H14N2·0.5H2O) and 1-methyl-2-(4-methylphenyl)-1H-perimidine (2, C19H16N2), were prepared and characterized by 1H NMR and single-crystal X-ray diffraction. The organic molecule of the hemihydrate lies on a twofold rotation axis while the water molecule lies on the intersection of three twofold rotation axes (point group symmetry 222). As a consequence, the hydrogen atoms that are part of the N—H group and the water molecule as well as the CH3 group of the p-tolyl ring are disordered over two positions. In compound 1, the perimidine and the 2-aryl rings are slightly twisted while its N-methylated derivative 2 has a more distorted conformation because of the steric repulsion between the N-methyl group and the 2-aryl ring. In the crystal structures, molecules of perimidine 2 are held together only by C—H...π contacts while the parent perimidine 1 does not exhibit this type of interaction. Its crystal packing is established by intermolecular N—H...O hydrogen bonds with the solvent water molecules and additionally stabilized by π–π stacking.

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