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Vapor Pressure Calculator

Blue fields allow input; press <RETURN> to calculate.

Temperature K
Vapor Pressure
Gas Density per m³ *
Evaporation/Subl. Rate per (m²s) **
Erosion m/s **
Melting Temperature K
Vapor pressure at Melting P.

Start Temperature T1= K
End Temperature T2= K
Temperature Step= K


Accuracy: For many substances, vapor pressures are only poorly known; expect errors up to a few 10% of the vapor pressure value. Errors can be much larger for very low vapor pressures, but also for high temperatures (up to approx. 10% of the temperature at high temperatures).

Note that for some substances, data are calculated only for the liquid state (Se, Bi, most organics) or only for the solid state (noble gases Ne-Xe, methane, I).

* Gas density in atoms or molecules per volume, assuming a monatomic gas unless the substance is given as molecule.
** Assuming evaporation/sublimation into vacuum, a sticking coefficient (accommodation coefficient) of one (not valid for, e.g., graphite), and a monatomic gas (unless the substance is given as molecule). Results will be inaccurate if there is a high fraction of dimers, trimers, etc (or other molecules than given) in the vapor. Erosion rates are very inaccurate (no temperature-dependent density) and only shown for vapor pressures below 1 Pa.

Data sources: Most metals use the fits from C.B. Alcock, V.P. Itkin, M.K. Horrigan, Canadian Metallurgical Quarterly, 23, 309 (1984). When these data were not available or unreliable (e.g. large difference between vapor pressure of the solid and liquid phase at the melting point), fits to values from the wikipedia table, the CRC Handbook of Chemistry and Physics (78th edition, 1997, CRC press) and other sources were used. Si and Fe data from P.D. Desai, J. Phys Chem Ref Data 15, 967 (1986); Ru, Rh, Pd, Os, Ir, Pt data based on J. W. Arblaster, Platinum Metals Rev. 51, 130 (2007). Data for liquid H2O based on a fit to the ITS-90 table supplemented with a few points up to 1 MPa.

Copyright © by Michael Schmid, IAP/TU Wien Surface Physics Group 2013-2023. No warranty for correctness of results.

surface/vapor_pressure.txt · Last modified: 2024-01-24 19:29 by Michael Schmid