crystal structure and imperfection of the perovskite-like proton conductor ba4ca2nb2o11

The crystal structure complex oxide Ba4Ca2Nb2O1 inanhydrous and hydrated forms was studied by the method of neutron diffraction, the preferred localization of protons were set. The hydration process with temperature variation and the partial pressure of water vapor was studied. It is established that the crystallographic non-equivalence OH-groups in the structure determines their different thermal stability. The quasi-chemical approach was proposed that describes the formation of proton defects in oxides with structural disordering.