A waveguide reactor for IR multiphoton dissociation and its application to¹³C laser isotope separation

Abstract

A waveguide reactor for infrared multiphoton dissociation reactions has been presented and applied to laser isotope separation of¹³C. The reactor is a sealed vessel containing a hollow waveguide for a CO₂ laser, and the laser beam is condensed in the waveguide. The waveguide is a pipe of total-reflection glass or metal-coated glass with a funnelled inlet; it is 50 cm long with a 3 mm inner diameter. The isotope separation of¹³C has been made by multiphoton dissociation of CHF₂Cl using a TEA CO₂ laser. The result has shown that the waveguide reactor increases the dissociation yield by four to ten times as much as that without the waveguide at the pulse rate of up to 150 Hz, while the separation factor remains on the same level. It is also found that an optical breakdown which is induced at the wall surface plays a significant role to reduce the isotope selectivity.