On a lead nickel manganese tellurium oxide PbMn2Ni6Te3o18 containing Mn2+ in trigonal prismatic oxygen coordination

A new lead manganese nickel tellurium oxide PbMn2Ni6Te3O18 is light green in color and crystallizes in hexagonal symmetry, space group C6h2 P63/m (no. 176), with cell parameters a = 9.294(1), c = 8.823(1) Å, and Z = 2. The structure was determined from a single crystal X-ray study and refined to the conventional values R = 0.026 and wR(F2) = 0.046. Ni2+ and Te6+ show octahedral and Mn2+ shows trigonal prismatic coordination by O2−. The crystal structure is featured by a ∞2[Ni6Te3O18]6− network together with two kinds of channels along [001] with trigonal and hexagonal shape. Isolated face shared [Mn2O9]14− trigonal prismatic polyhedra doubles are located in the trigonal channels, while one-dimensional infinite chains of [PbO6+6]22− oxygen cube dodecahedra are incorporated in the hexagonal channels.