Role of local structural distortion in driving ferroelectricity in GdCrO sub(3)

Abstract

Temperature-dependent synchrotron x-ray diffraction and extended x-ray absorption fine structure (EXAFS) studies were performed to understand the role of structural characteristics in driving the magnetoelectric multiferroic properties of GdCrO sub(3). The results suggest that the distortion in the structure appears to be associated with the off-center displacement of Gd atoms together with octahedral rotations via displacement of the oxygen ions in GdCrO sub(3). Further, a comparative EXAFS study of GdCrO sub(3) with a similar system, YCrO sub(3), suggests that the oxygen environment of Gd in GdCrO sub(3) is different from that of Y in YCrO sub(3), which results in an orthorhombic Pna2 sub(1) structure in GdCrO sub(3) in contrast to the monoclinic P 2 1 structure in YCrO sub(3).