E. G. Boonstra
Aug 1, 1963
Citations
1
Influential Citations
26
Citations
Journal
Acta Crystallographica
Abstract
A_ more detailed account of the redetermination of the structure of 4,4'-dinitrodiphenyl, briefly reported earlier by van Niekerk & Boonstra (1961), is given. The structure was obtained by a combination of Patterson and intensity-distribution methods, and has now been refined by fullmatr ix least-squares analysis with individual isotropic temperature factors for non-hydrogen atoms. The residual R, based on 650 hlcl reflexions (including 250 unobserved reflexions) has been reduced to 15%. The molec~de is neither centrosymmetric nor planar as the approximately planar benzene rings are twisted about the central C-C bond through about 33 °, relative to each other. The length of this bond is 1.499 /~, with an e.s.d, of 0.016 A. The atomic coordinates (e.s .d._ 0.02 A) are not known accurately enough to permit discussion of the variation of bond lengths. I t is suggested that intermolecular bonding may be due to a weak type of C-H • • • O bond. The temperature motion is not discussed.