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Samples of SrFe1-xTixO3-δ (x = 0-0.3) are prepared by sol-gel reaction of stoichiometric amounts of Sr(NO3)2, Fe(NO3)3,Ti(O-iPr)3, and citric acid in a 2:1 EtOH/H2O solution followed by firing of the obtained gel and sintering of pressed pellets (1300 °C, 17 h).

A composite of the electronic conductor α-LiFeO2 and the insulator γ-LiAlO2 is prepared by solid state reaction of a 1:0.7:0.3 molar mixture of Li2CO3, Fe2O3, and Al2O3 (900 °C, 1 h).

Co2V2O7 is synthesized by solid state reaction of CoCO3 and V2O5 (600 °C, 7 d) and characterized by XRD and conductivity measurements in oxidizing as well as reducing environments.

A novel bismuth calcium vanadate, Bi 4.6 Ca 1.1 VO 10.5 , has been synthesized. Its crystal structure has been determined by synchrotron X-ray diffraction. The compound crystallizes in orthorhombic space group Pnnm, with cell parameters a = 11.930(2) A, b = 16.030(3) A, and c = 11.500(2) A. The crystal structure can be viewed as consisting of fluorite-like slabs of edge-sharing OA4 (A = Bi, Ca) tetrahedra that extend along the c axis of the crystal and interspersed disordered VO 4 groups. Bi and Ca atoms undergo site disorder, with Bi preferentially occupying locations with low site symmetry and irregular coordination environments. Variable temperature powder diffraction measurements reveal a change in the thermal expansion coefficient of Bi 4.6 Ca 1.1 VO 10.5 above 600 °C and this coincides with the change in conductivity as revealed by a.c. impedance measurements.