In most literature, I have read on Bi4Ti3O12 thin films, the presented XRD is commonly have very intense (117) orientated peaks. I understand that if I film have no matching lattice dimensions with its substrate, it grows along the smaller of its axis to minimise surface energy (BTO, a = 0.545nm, b = 0.541nm, c=3.282nm), this being the case, I would expect there to be strong (004) or (008) orientations when there is no match, however (117) is the most commonly reported one in the literature. Can anyone explain to me why this is?
Many Thanks
David Coathup