On the 180°-type Domain Wall of BaTiO3Crystal

The energy of the 180°-type domain wall of BaTiO 3 crystal is obtained as 1.4 erg/cm 2 considering the dipole interaction and other interatomic energy of Born type. The dipole interaction term has been obtained approximately from the difference of the energy of ferroelectric and antiferroelectric (stripes type) dipole configurations. The wall is found to be quite thin, that is, the change of polarization at the boundary is abrupt, in contrast with the ferromagnetic walls. The structure of the 180° domains and their reversing process are also discussed.