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Calculated Diffusivities for Water Isotopologues in Carbon Dioxide, Nitrogen, and the Atmosphere of Mars, and for Methane Isotopologues in Nitrogen Representing the Atmosphere of Titan

Published by National Institute of Standards and Technology | National Institute of Standards and Technology | Metadata Last Checked: August 02, 2025 | Last Modified: 2021-04-19 00:00:00
Values are computed for the dilute-gas diffusivity of water isotopologues in N2, CO2, and their mixture at a composition representing the atmosphere of Mars, for standard conditions of 101.325 kPa and water mole fraction approaching zero. Values are similarly computed for the diffusivity of methane isotopologues in N2, representing the atmosphere of Titan. Calculations employ state-of-the-art intermolecular potentials and classical trajectory calculations as described in the paper by R. Hellmann and A.H. Harvey, "First-Principles Diffusivity Ratios for Atmospheric Isotope Fractionation on Mars and Titan", published in Journal of Geophysical Research: Planets, 126, e2021JE006857 (2021), https://doi.org/10.1029/2021JE006857. Separate files are given for the diffusivities of H2O, HDO (where D is deuterium), and the 17-O and 18-O substitutions of H2O, and for the diffusivities in N2 of CH4, CH3D, and the 13-C substitution of CH4.

Resources

17 resources available

  • DOI Access for Calculated Diffusivities for Water Isotopologues in Carbon Dioxide, Nitrogen, and the Atmosphere of Mars, and for Methane Isotopologues in Nitrogen Representing the Atmosphere of Titan

    FILE
  • DIffusivity of H2O

    APPLICATION/OCTET-STREAM
  • Diffusivity of HDO

    APPLICATION/OCTET-STREAM
  • Diffusivity of 13-CH4

    APPLICATION/OCTET-STREAM
  • Diffusivity of CH3D

    APPLICATION/OCTET-STREAM
  • Diffusivity of CH4

    APPLICATION/OCTET-STREAM
  • Diffusivity of H2-17O

    APPLICATION/OCTET-STREAM
  • Diffusivity of H2-18O

    APPLICATION/OCTET-STREAM
  • Readme file

    TEXT/PLAIN
  • SHA256 File for Diffusivity of 13-CH4

    TEXT/PLAIN
  • SHA256 File for Diffusivity of CH3D

    TEXT/PLAIN
  • SHA256 File for Diffusivity of CH4

    TEXT/PLAIN
  • SHA256 File for Diffusivity of H2-17O

    TEXT/PLAIN
  • SHA256 File for Diffusivity of H2-18O

    TEXT/PLAIN
  • SHA256 File for DIffusivity of H2O

    TEXT/PLAIN
  • SHA256 File for Diffusivity of HDO

    TEXT/PLAIN
  • SHA256 File for Readme file

    TEXT/PLAIN

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