Multi-isotope study of fractionation effects in the ozone formation process

The isotope fractionation of all ozone isotopologs of mass 48-54 u has been measured with high accuracy. The data represent a standard for the magnitu de of the ozone isotope effect since pressure, temperature, and composition of the gas in which ozone is produced are well known. While (OOO)-O-17-O-1 7-O-17 and (OOO)-O-18-O-18-O-18 are depleted by -1.5% and -3.9%, respective ly, all others are enriched with (OOO)-O-16-O-17-O-18 showing the highest v alue of 19.8%. Enrichments or depletions are independent of the isotope com position of the oxygen gas. (C) 2000 American Institute of Physics. [S0021- 9606(00)00631-0].