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Artículo
Molecular-Packing Analysis of Some Glucofuranoimidazolidine Crystals
(International Union of Crystallography, 1987)
Lattice-energy minimization for seven glucofuranoimidazolidine crystals was carried out in the atom-atom approach using an (exp-6-1) form for atom-pair interactions. Molecular rotation and translation and also internal ...
Artículo
Molecular Packing in Crystals of Phenoselenazine
(International Union of Crystallography, 1976)
The crystal structure of phenoselenazine was solved by molecular-packing analysis. Trial models of the rigid molecule were oriented and positioned in the Cheshire cell. The refinement was carried out by structure-factor ...
Artículo
Lattice-Energy Calculations on Phenothiazine and Phenoselenazine Modifications
(International Union of Crystallography, 1983)
Lattice-energy calculations in the atom-atom potential approach have been performed for observed and isostructurally derived hypothetical forms of phenothiazine and phenoselenazine compounds. Energy minimizations with ...
Artículo
The Crystal and Molecular Structure of 1-p-Chlorophenyl-4-(tt-a-erythrofuranosyl)-4-imidazoline-2-thione
(International Union of Crystallography, 1974)
The title compound, CISOsN2C~sH~3, the definitive formula of which has been established by X-ray structural analysis, is orthorhombic, space group P2~2121 with a= 7.806 (5), b= 29.417 (13) and c= 5-921 (5) A, Z--4. The ...
Artículo
Structure of l'-(p-Bromophenyl)-3'-ethyl- 1',3t,4',5 t -tetrahydro- 1,2-¢~• deoxy-D-glyeero-Dgu/ a-heptofuranoso[ 1,2-d]imidazole-2'-thione,* C16H21BrN2OsS
(International Union of Crystallography, 1984)
M r = 433.3, monoclinic, P21, a = 6.924 (3), b=8.661 (1), c=15.039(3)A, #=96.92(3) ° , v= 895.3 (4) A a, Z= 2, D, = 1.598 (5), Dx= 1.607 Mg m -a, Mo Ka, 2 = 0.7107/k, # = 2.42 mm -1, F(000) = 444, T = 300 K, R = 0.039 ...
Artículo
Lattice Dynamical Calculation of First-Order Thermal Diffuse Scattering in Phenothiazine
(International Union of Crystallography, 1985)
A computer program has been developed to calculate first-order thermal diffuse scattering (TDS) intensity from eigenvectors and eigenvalues of the dynamical matrix obtained within the harmonic approximation with an ...
Artículo
Structure of 1,3-Dihydro-4-[(2R)-2,5-dihydro-2-furyl]-3-phenyl-l-(p-tolyl)-2H-imidazole- 2-thione, C20HlsN2OS
(International Union of Crystallography, 1985)
Mr=334.4, orthorhombic, P212~2 ~, a= 9.366(4), b=20.616(5), c=9.137(4)A, V= 1764 (1) A 3, Z = 4, D x = 1.26 Mg m -3, 2(Mo Ka) = 0.7107 A, g = 0.18 mm -~, F(000) = 704, T= 300 K, final R--0.056 (wR =0.052) for 1979 ...
Artículo
The Crystal and Molecular Structure of 2-Formylpyridine Selenosemicarbazone
(International Union of Crystallography, 1972)
The structure of 2-formylpyridine selenosemicarbazone, SeN4CTH8, has been determined from threedimensional X-ray photographic data. The crystals are monoclinic, space group P2t/e, with unit-cell dimensions a=9.320, b=6-524 ...
Artículo
X-Ray Structure of 8alpha-Acetoxy-1,3,4,10-Tetrahydro-1alpha,10alpha-Epoxyachillin
(International Union of Crystallography, 1986)
(5aI-I,6/~-I, 11 aH)-8a-Acetoxy- 1,5-dihydro-2- oxo-lct,10ct-epoxyguaian-6,12-olide, C~7H2206, Mr= 322.3, orthorhombic P2~212~, a= 14.964(6), b= 17.057(4), c=6.218(4)A, V=1587(1)A 3, Z=4, D,n=l.349(5), D x=l.349Mgm -3, ...
Artículo
The Crystal and Molecular Structure of 4-Formylimidazoline-2-thione
(International Union of Crystallography, 1977)
The title compound is monoclinic, space group P2 Jc, with a = 4.020 (4), b = 21.491(3), c = 7-410 (4) ,4,, fl = 124.1 (5) °, Z = 4. The structure was solved by Patterson-function and heavy-atom methods from diffractometer X-ray ...