5-Iodobenzofurazan 1-oxide: polymorphs, pseudosymmetry and disorder.
5-Iodobenzofurazan 1-oxide (systematic name: 5-iodobenzo-1,2,5-oxadiazole 1-oxide), C(6)H(3)IN(2)O(2), occurs in two polymorphic forms, both monoclinic in P2(1)/c with Z' = 2. The intermolecular interactions in the two polymorphs are quite different. In polymorph (I), there are strong intermolecular I...O interactions, with I...O distances of 3.114 (8) and 3.045 (8) A. In polymorph (II), there are strong intermolecular I...N interactions, with I...N distances of 3.163 (4) and 3.175 (5) A. In (I), there is about 15% disorder in one molecule and about 5% in the other. In both polymorphs, there are pseudosymmetric relationships between the crystallographically independent molecules.
Britton
Doyle
D
Department of Chemistry, University of Minnesota, Minneapolis, MN 55455-0431, USA. britton@chem.umn.edu
Noland
Wayland E
WE
Clark
Christopher M
CM