Raman Spectroscopy of CaTiO₃-Based Perovskite Solid Solutions

H. Zheng, University of Sheffield
I.M. Reaney, University of Sheffield
G. D.C. Csete de Györgyfalva, University of Sheffield
Rick Ubic, Boise State University
J. Yarwood, Sheffield Hallam University
M. P. Seabra, University of Aveiro
V. M. Ferreira, University of Aveiro

Abstract

Perovskite-structured solid solutions intended for use as microwave dielectric resonators were studied by Raman spectroscopy. Two distinct categories were investigated: (i) simple perovskite–simple perovskite solid solutions, that is, CaTiO₃–SrTiO₃ (CTST), CaTiO₃–CaZrO₃ (CTCZ), CaTiO₃–NdAlO₃ (CTNA), and CaTiO₃–LaGaO₃ (CTLG); and (ii) simple perovskite–complex perovskite solid solutions, such as CaTiO₃–SrMg_1/3Nb_2/3O₃ (CTSMN). In the latter category, the influence of A-site ion radius was also addressed by examining 0.5CaTiO₃– 0.5LaMg_1/2Ti_1/2O₃ (0.5CT–0.5LMT), 0.5SrTiO₃ (ST)–0.5LMT, and 0.5BaTiO₃ (BT)–0.5LMT. Raman data from the end members and solid solutions are compared, paying particular attention to F _{2 g} and A _{1 g} mode bands, often associated with ordering of B-site species.