Pb(OH)(2) was previously proposed as an intermediate in the synthesis of PMN [Pb(Mg1/3Nb2/3)O-3] and PMN-PT [0.9Pb(Mg1/3Nb2/3)O-3-0.1PbTiO(3)] from a mixture of PbO, Nb2O5, Mg(NO3)(2)(.)6H(2)O (w/w(0)) TiO2 by the modified mixed oxide method based on TG/DSC and XRD data. Coupled TG-MS of the precursor reveals that the intermediate is Pb6O5(NO3)(2), not Pb(OH)(2) because the evolved gas was nitric oxide and oxygen, not water. (c) 2005 Elsevier B.V. All rights reserved.