SOLUTION ROUTES TO LEAD TITANATE - SYNTHESIS, MOLECULAR-STRUCTURE ANDREACTIVITY OF THE PB-TI AND PB-ZR SPECIES FORMED BETWEEN VARIOUS LEAD-OXIDE PRECURSORS AND TITANIUM OR ZIRCONIUM ALKOXIDES - MOLECULAR-STRUCTURE OF PB2TI2(MU(4)-O)(OAC)(2)(OPRI)(8) AND OF PBZR3(MU(4)-O)(OAC)(2)(OPRI)(10)

The reactions between Ti(OR)(4)(R=Et, Pr-i) or [Zr(OPri)(4)((PrOH)-O-i )](2) and various lead oxide precursors [anhydrous Pb(OAc)(2), alkoxid es or oxoalkoxides] have been investigated in different experimental c onditions (solvent, temperature). Various mixed-metal species have bee n isolated in high yields and characterized by microanalysis, FTIR and multinuclear NMR (H-1, C-13 and (207)pb) spectroscopies The mixed-met al oxoacetatoalkoxides Pb2Ti2(mu(4)-O)(mu-OAc)(2)(mu-OPri)(5)(OPri)(3) 1 and PbZr3(mu(4)-O)(mu-OAc)(2)(mu-OPri)(5)(OPri)(5) 2 have been char acterized by X-ray crystallography at -100 degrees C: for 1, monoclini c, space group C-2/c with a=38.916(17)Angstrom, b=12.045(2)Angstrom, c =19.046(4)Angstrom, beta=112.84(3)degrees, V=8224(4)Angstrom(3), Z=8, R=0.068, R-W=0.076; and for 2, monoclinic space group P2(1)/n with a=1 0.618(2)Angstrom, b=25.157(11)Angstrom, c=18.611(5)Angstrom, beta=90.3 5(2)degrees, V=4971(3)Angstrom(3), Z=4, R=0.060, R-W=0.072. Hydrolysis -condensation reactions have been achieved especially for the species having a Pb:Ti stoichiometry appropriate for access to PbTiO3. Effects of the solvent on the temperature of crystallisation and on the parti cle size are discussed.