A neutron diffraction study of 1,1'-ethylenebis(piperidine 1-oxide) monoperchlorate

C12H25N2O2+.ClO4- [PEtP(NO)2.HClO4], triclinic, P-1, a = 6.281(1), b = 12.443(1), c = 10.490(1) A, α = 102.48(1), β = 99.18(1), γ = 85.84(1)0, Z = 2, μ(measured) = 0.285 mm-1 for lambda = 1.210 A. Final R = 0.060 for 2037 reflexions and 416 parameters. The intramolecular O...H...O bridge is 2.429(5) A with an O...H...O angle of 175.1(6)0. The proton is, within experimental error, centrally located in the bridge, the two O...H distances being 1.225(7) and 1.206(7) A. Thermal motion within the hydrogen-bond bridge indicates a single-minimum potential well. The geometry of the PEtP(NO)2 skeleton is practically identical with that deduced from X-ray data. (Auth.)