Abstract
The structural characteristics of Pb(M1−x M)O3 solid solutions, with M, M′=Ti, V and Cr, have been investigated by powder X-ray diffraction. The specimens studied were synthesized under high pressure and high temperature in a ‘belt-type’ apparatus. The analogy between polymorphic, compared with the PbTiO3 (tetragonal↔cubic phase transition), and morphotropic transformation in these systems is sufficiently close so as to be able to use the Birch–Murnaghan equation of state of PbTiO3 and relate it to the internal (or the so-called ‘chemical’) pressure generated by the substitution of vanadium or chromium along the different solid solutions.
Acknowledgements
Samples were obtained at LABCOAP (http://www.ucm.es/info/labcoap/index.htm) with the help of Dr Jose Manuel Gallardo Amores. A.M.A.-L. acknowledges CONACYT for a PhD grant. This work was funded by CICYT (Project MAT2007-64007), Comunidad Autónoma de Madrid (Program MATERYENER, PRICYT S-0505/PPQ-0093,2006) and Fundación Areces (Ayudas 2004): ‘Física de bajas temperaturas’.