ISSN:
1572-8854
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
,
Physics
Notes:
Abstract Benzylidenemalononitrile, C10H6N2 crystallizes in the monoclinic space group,P21/c;a = 9·385,b = 3·976,c = 22·152 Å, β = 93·53 °,V c = 825·03 Å3,D m = 1·231,D c = 1·242 g cm−3,Z= 4. The structure was solved by fitting cojointly an assumed molecular shape to both the near-origin peaks of the sharpened vector map and the distribution in the Harker (U,1/2,W) section, followed by trial-and-error establishment of the γ coordinates. The structure was then refined by full-matrix least squares, reducingR to 0·090 for data comprising 1412 reflexions (0·086, omitting 373 unobserved) from room temperature CuKα Weissenberg photographs. Steric hindrance of the malononitrile group and a hydrogen atom in theortho position of the phenyl ring causes simultaneous expansion of the bond angles between the malononitrile group and the benzylidene group and rotations of these groups relative to each other. These constraints cause the two groups to be non-planar, the dihedral angle between their least-squares planes being 11·0 °.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01198366
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