A Lead PhosphoMolybdenum Purple Bronze: Pb0.9PMo₅O₁₇

A phosphomolybdenum bronze containing lead, Pb 0.9 PMo 5 O 17,has been synthesized for the first time. It crystallizes in the space group P 3̄ m 1, with a = 5.415(1) Å and c = 13.476(2) Å. Its crystal structure, close to that of the charge density wave (CDW) bronze Na 0.9 Mo 6 O 17, differs from the latter by the occupation of one crystallographic site by P and Mo simultaneously and by the position of Pb 2+ cations, which are distributed over 12 split sites because of the stereoactivity of the 6s 2 lone pair of Pb 2+ . The calculation of the density of states predicts a metallic behavior in agreement with the Pauli paramagnetic susceptibility for T > 75 K. The resistivity measured versus T on a polycrystalline bar is explained as the result of grain boundary effect, preventing the metal-like behavior from being evidenced. No sign of a CDW could be detected.