Abstract
Substances containing Hydrogen bond show phase transitions of various types. Among them, those undergoing frerroelectric phase transitions attract attention of scientists because of its drastic change in physical properties and its simplicity in model accessible by theoretical method. Due to its difference in scattering power of hydrogen atom for X-rays and for thermal neutrons, application of neutron diffraction technique to this field becomes increasing. Single crystal neutron diffraction studies on this subject carried out at Kyoto University Reactor (KUR) are mainly reviewed. Starting from neutron diffraction apparatus, recent development in hydrogen bond studies, analysis of ferroelastics, problems in deuterium substitution, agreement factor in structure analysis are discussed. Survey is also given on some of the non-hydrogen-bonded ferroelectrics.
