A new class of flexible energetic salts, part 6: the structures of the hydrazinium and hydroxylammonium salts of dinitramide

The crystal structures of two amine base salts, the hydrazinium, 1, and the hydroxylammonium, 2, of dinitramide have been determined. I crystallizes i n the monoclinic space group P 2(1)/c with cell dimensions a = 8.312(3), b = 5.654(1), c = 10.659(3) Angstrom, beta = 93.73(3)degrees, while 2 crystal lizes in the orthorhombic space group Pcab (nonstandard setting of Pbca) wi th cell dimensions a = 6.439(2), b = 12.470(4), c = 30.816(14) Angstrom. Th e structures of 1 and 2 contain protonated amine cations and dinitramide an ions linked by hydrogen bonding. In addition, in 2 there are both neutral a nd zwitterionic hydroxylamine moieties involved in the hydrogen bonding sch eme. Thus in 2 the complete formula unit is (NH3+OH)(2)[N3O4-](2) . (NH2OH) . (NH3+O-), and in this structure the hydroxylamine exists in its three po ssible forms: protonated, neutral, and zwitterionic. In both structures the conformations adopted by the dinitramine anions can be related to the type s of hydrogen bonds it forms with the surrounding amine cations.