Changes in ordered structure and dielectric properties with the A-site and B-site cation ratios of complex perovskites (Sr_(1-x)Ba_x)(Sr_(0.33+y)Ta_(0.67-y))O_(3- delta )

摘要

Complex perovskites with large-sized B'-site cations, (Sr_(1-x)Ba_x)(Sr_(0.33+y)Ta_(0.67-y))O_(3- delta )(0<=x<=1, 0<=y<=0.17), were fabricated to examine the transformation behavior between the (1:1) and (1:2) order types and dielectric property change with A-site cation substitution. The (1:2) type order was found to appear in a limited Ba-rich composition range. Structural strain induced by size difference between the A-site and large-sized B'-site cations might be responsible for the occurrence of the (1:1) type order in perovskite compounds substituted with more than 50