Ferroelectric domain walls in BaTiO3: Structural wall model interpreting fingerprints in XRPD diagrams

Accurate analyses of X-ray diffraction patterns of micrometric BaTiO3 grain s has shown that 90 degrees domain wall is not a single twin (101) plane bu t a few nanometers wide region where the twinning crystallographic disconti nuity could be accommodated by atom plane translations. A structural model of the 90 degrees domain wall based on curved (001) and (100) planes is pro posed. Its theoretical diffraction treatment is developed. The good agreeme nt between experimental fingerprints and theoretical line profiles allows t o propose a wall thickness of around 140 Angstrom for micrometric BaTiO3 gr ains whereas their domain thickness is of the order of 0.1 mu m.