  Room temperature Co K-edge extended x-ray absorption fine structure (EXAFS),
x-ray absorption near edge structure (XANES) including pre-edge and x-ray
diffraction (XRD) studies are carried out on LaCoO3 and PrCoO3. The Co-O,
Co-La/Pr and Co-Co bond lengths are obtained from EXAFS analysis and compared
with those obtained from XRD. The EXAFS analysis of data indicates that CoO6
octahedron is distorted in both LaCoO3 and PrCoO3. Such distortion is expected
in orthorhombic PrCoO3 but not in rhombohedral LaCoO3. This distortion in CoO6
octahedron is attributed to Jahn-Teller active Co3+ ion in intermediate spin
state in these compounds. Higher shell studies reveal that Debye-Waller (DW)
factors of Co-Pr and Co-Co bonds in PrCoO3 are more in comparison to Co-La and
Co-Co bonds in LaCoO3 indicating that these bonds are structurally more
disordered in PrCoO3. The comparison of Co-Co bond lengths and corresponding DW
factors indicates that the structural disorder plays an important role in
deciding the insulating properties of these compounds. XANES studies have shown
changes in the intensities and positions of different near edge features.
