Mechanism by Neutron Diffraction

However, the neutron diffraction analysis of the crystal after photo-irradiation has two difficulties (1) a very large crystal ( 5 mm ) is required due to the weak intensity of the neutron beam and (2) the visible light must penetrate into the crystal and the photoreaction must occur uniformly inside the crystal without deteriorating the crystallinity. 

3 Racemizations of Alkyl Groups in Cobaloxime Complex Crystals 

A crystal of 3.0 x 3.0 xO.6 ( 5.4)mm was prepared for the pyridine complex and the crystal was irradiated with a fluorescent lamp for 36 h, while a crystal of 

0) mm was exposed to a xenon lamp for 28 days for the piperidine complex [10], The intensity data were collected on the BIX-1 diffractometer at the JRR-3M reactor of the Japan Atomic Energy Research Institute (JAERI). The crystal structures of the pyridine and piperidine complexes after photo-irradiation determined by nentron diffraction are essentially the same as those by X-ray diffraction. 

For the piperidine complex, almost 50 % of the 1-ce group of B was inverted to the opposite R configuration. The D9 atom is completely bonded to the chiral carbon atom, C9. No H/D exchange with the methyl hydrogen atoms was observed in the 1-ce group of B. 

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