title: Simultaneous measurement of δ2H, δ17O, and δ18O in H2O using a commercial cavity ringdown spectrometer.
abstract: We demonstrate that a commercial instrument that provides measurements of (18)O/(16)O and D/H ratios in water samples can be modified to also provide measurements of (17)O/(16)O. This additional capability and associated precision allows for the discernment between conventional mass-dependent processes, such as isotope exchange and evaporation and mass-independent processes that arise from non-equilibrium chemical and photochemical processes. We demonstrate this resolution by performing a series of experiments including evaporation and reservoir-mixing with (17)O enriched water samples followed by evaporation. The ability to simultaneously measure (16)O, (17)O, and (18)O abundances in water samples using the procedures described here should help to facilitate multi-isotopic studies of water (and other compounds) in astrochemical, geochemical, and biological studies.
authors.affiliation: Department of Physics, California State University, San Marcos, San Marcos, CA, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Salvo
authors.forename: John
authors.initials: J
authors.lastname: Gormally
authors.forename: Gerardo
authors.initials: G
authors.lastname: Dominguez
keywords: CRDS; Fractionation; Hydrogen; Isotopes; Oxygen; Water