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Acta Cryst. (2008). E64, o1428 [ doi:10.1107/S1600536808019727 ]

Redetermination of cyclo-trimethylenetrinitramine

P. Hakey, W. Ouellette, J. Zubieta and T. Korter

Abstract: The redetermined structure of 1,3,5-trinitro-1,3,5-triazacyclohexane, C₃H₆N₆O₆, at 90 (2) K has orthorhombic (Pbca) symmetry. It is of interest with respect to energetic compounds. The structure was originally investigated through X-ray diffraction by Hultgren [(1936). J. Chem. Phys. 4, 84]. Later X-ray investigations were completed by McCrone [(1950). Anal. Chem. 22, 954-955] and Harris, Reed & Gluyas [(1959). AFOSR-TR-59-165 Ohio State University Research Foundation, Columbus, Ohio, USA]. A single-crystal neutron diffraction study was performed by Choi & Prince [(1972). Acta Cryst. B28, 2857-2862] to ascertain the H-atom positions, which had not been defined by the earlier X-ray diffraction studies. All previous studies were performed at or near room temperature. The structure provided is the [alpha] polymorph of the title compound. The ring atoms are arranged in the chair conformation with two nitro groups occupying pseudo-equatorial positions and the remaining nitro group is axial. The crystal packing is stabilized by close intramolecular interactions from one H atom in each methylene group to O atoms of adjacent nitro groups, ranging from 2.251 to 2.593 Å.

Online 9 July 2008