Crystal chemistry of lead oxide hydroxide nitrates I. The crystal structure of [Pb6O4](OH)(NO3)(CO3)

The new lead oxide hydroxide nitrate carbonate, [Pb6O4](OH)(NO3)(CO3), has been synthesized by hydrothermal methods. The crystal structure has been de termined by single-crystal X-ray diffraction and refined to R1 = 0.030. The compound is orthorhombic, space group Pnma, a = 30.557(6), b = 5.809(1), a nd c = 7.183(2) Angstrom, V = 1274.9(5) Angstrom(3), Z = 4. The structure c onsists of (OPb4) oxocentered tetrahedra linked via edges into double [O2Pb 3] chains running along the b axis. These chains are linked via (OH)Pb-2 di mers into layers parallel to the (100) plane. (NO3) and (CO3) groups are pa rallel to the (010) plane and are located between the Pb-(O, OH) layers. Pb coordination polyhedra are strongly distorted due to the influence of lone -pair electrons. The presence of the nitrate, carbonate, and (OH)(-) groups has been confirmed by Fourier transform infrared spectroscopy, (C) 2000 Ac ademic Press.