Pulsed infrared carbon selective dissociation of CF3Br with N2 and D2 as buffers

The pulsed IR photodissociation of CF3Br mixtures 1:3 with D2 and N2 has been studied as a function of pressure, temperature, fluence and wavelength. The results have been analyzed by mass spectrometry and compared with those obtained for the pure substance and a 1:3 hydrogen mixture. In all cases, maximum enrichment for carbon-13 is obtained when irradiating with the 1046.9 cm−1 (9P20 CO2) laser line. The enrichment factor tends towards 1 as the pressure is increased. It seems that deuterium and nitrogen have a buffer effect less remarkable than hydrogen. For all the mixtures and the most selective wavelengths, enrichment improves when the fluence increases from 0.98 to 1.7 J/cm2 and when the temperature decreases from 22 to −85°C.