A novel Mo(V) monophosphate with Bromine and mixed valent Lead and a PbO double bond: Pb2+(Pb4+O)Br(Mo5+O)2(PO4)3

A novel molybdenum(V) monophosphate containing bromine and mixed valent lead, Pb2+(Pb4+O)Br(Mo5+O)2(PO4)3, has been synthesized for the first time. It crystallizes in the orthorhombic space group Fdd2 with a=31.721(7)A, b=12.931(2)A, c=12.905(2)A. Its frameworks built up from [Mo2P2O12]{infinity} perovskite type layers connected through phosphate groups, delimits tunnels in which the Pb2+ and the Pb4+ cations and the Br- anions are sitting. The Pb4+ specie is connected to one isolated oxygen atom via a double bond forming a PbO 'Leadyl' group. The divalent lead ions bonded to the bromine ions form infinite PbBr ribbons running along b in the tunnel. On these ribbons are scratched the Leadyl groups.