Isotopically selective infrared multiphoton dissociation of 2,3-dihydropyran

Yokoyama, Atsushi; Katsumata, Keiichi*; Oba, Hironori  ; Akagi, Hiroshi; Saeki, Morihisa; Yokoyama, Keiichi  

Oxygen isotope separation has been examined by using an infrared multiphoton dissociation of 2,3-dihydropyran. Enrichment factor has been measured by the CO laser irradiation of the samples as a function of laser frequency, laser fluence, and sample pressure. Maximum enrichment factor of 751 has been obtained, and O, natural abundance of which is 0.205 %, was enriched to 60 %. Moreover, it was found that the enrichment factor increases with increasing the sample pressure, which was different from the infrared multiphoton dissociation of usual molecules. This phenomenon was discussed on the basis of a simulation by a rate equation model including a collisional vibrational relaxation.