CRYSTAL AND MOLECULAR STRUCTURE OF TWO MODIFICATIONS OF BIS-(2,2,2-TRINITROETHYL)NITRAMINE

Article abstract of DOI:10.1007/BF00745733

The structure of the two modifications of bis-(2,2,2-trinitroethyl)nitramine have been studied.The crystals of modification A are orthorhombic, a = 22.995, b = 9.506, c = 6.147 Angstroem, d_calc = 1.929 g/cm³, space group Pn2₁a, four molecules in the unit cell.The crystals of modification B are monoclinic, a = 18.124, b = 10.362, c = 6.162 Angstroem, γ = 118.65 deg, d_calc = 1.967 g/cm³, space group P2₁/a, four molecules in the unit cell.The structures were determined from the intensities, recorded on a DAR-UM diffractometer, and refined by the method of least squares as far as R = 0.055 for 572 and 1988 reflections respectively.The intramolecularand intermolecular contacts in both modifications have been examined.On going from modification A to modification B there is slight loosening of the molecule, leading to a decrease in the intermolecular contacts.The molecules in modification B are less strained and more closely packed, leading to a slight increase in the density of the crystal.