Direct observation of crystalline-state reactions by single crystal neutron diffraction analyses

Ohara, Takashi   ; Hosoya, Takaaki; Ohashi, Yuji*

The exchange of some hydrogen atoms with the other hydrogen atoms in the crystalline-state reactions, in which the reaction proceeds with retention of the single crystal form, can be directory observed by single crystal neutron diffraction technique if only the transferred hydrogen atoms were replaced with deuterium atoms before the photoirradiation. The method was successfully applied in the photoisomerization of three kinds of cobalt complex crystals and the mechanism in each reaction has been made clear.