Abstract
The vapor pressure isotopic effect (VPIE) of xenon has been measured using cryogenic distillation. The still is calibrated with argon and krypton and yields a measurement of ln(p 130/p 136) ≃ (0.26 ± 0.04) × 10–3, where p 130 and p 136 are the vapor pressures of 130Xe and 136Xe at the nominal boiling point, respectively. The dependence of the VPIE across the isotopes for the three elements is found to be approximately linear with atomic mass, and all values are consistent with theoretical expectations.