The exact room-temperature crystal structure of sodium bismuth titanate has been a matter of debate for several years.
Early studies in the 1960s using X-ray diffraction suggested Na0.5Bi0.5TiO3 to adopt either a pseudo-cubic or a rhombohedral crystal structure.
[1] In 2010, based on the high-resolution single-crystal X-ray diffraction data, a monoclinic structure (space group Cc) was proposed.
[3] Various solid solutions with tetragonal ferroelectric perovskites including BaTiO3,[4] Bi0.5K0.5TiO3[5] have been developed to obtain morphotropic phase boundaries to enhance the piezoelectric properties of Na0.5Bi0.5TiO3.
The extraordinarily large strain generated by a field-induced phase transition in sodium bismuth titanate-based solid solutions prompted researchers to investigate its potential as an alternative to lead zirconate titanate for actuator applications.