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NIST Standard Reference Database 203 Web Thermo Tables (WTT) - Professional Edition

NIST Standard Reference Database 203 Web Thermo Tables (WTT) - Professional Edition

This web application provides access to a collection of critically evaluated thermodynamic property data for pure compounds with a primary focus on organics. These data were generated through dynamic data analysis, as implemented in the NIST ThermoData Engine software package. As of November, 2011, WTT - Professional Edition contains information on 23399 compounds and access to a total of 512538 evaluated experimental data points. This product also provides critically evaluated data for some non-molecular species such as radicals and organic salts carried from the TRC Thermodynamic Tables published from 1942-2009.

Various search options based on compound information (empirical formula, partial name, molecular weight) are provided. Data presentation features an interactive JavaScript-based Web interface with dynamic window-in-window navigation. Dynamic table generation based upon user input and interactive data plotting capabilities are also provided. Unlimited data retrieval and their local storage and use are permitted. For details regarding analytical methods and interacting with the interface, see the site user's guide.

Evaluated properties that appear in the WTT are (note that all listed properties are not necessarily available for all included compounds):

Critical Properties
Critical temperature
Critical pressure
Critical density

Phase Transition Properties
Triple point temperature
Boiling point
Vapor pressure
Sublimation pressure
Condensed-phase boundary pressure
Enthalpy of vaporization
Enthalpy of fusion
Enthalpy of crystalline phase transition

Volumetric Properties
Mass density
Isobaric coefficient of expansion
Isothermal compressibility
Thermal pressure coefficient
2nd virial coefficient
3nd virial coefficient
Adiabatic compressibility

Energetic Properties
Enthalpy of formation
Heat capacity at constant pressure
Heat capacity at constant volume
Heat capacity at saturation
Pressure coefficient of enthalpy
Joule-Thomson coefficient

Transport Properties
Thermal conductivity

Additional Properties
Speed of sound
Index of refraction
Surface tension

Complimentary WTT-Pro data availability information (properties provided for a given compound, ranges of validity, number of experimental data points) can be accessed by those without a subscription at

Click to view the subscription License Agreement before ordering.

Pricing Information:

Access to WTT - Professional Edition is subscription-based; the annual

license fees are listed below:
Individual License - Individual License $1200.00 Place Order

Small Institution - Small Institution (2 to 500 users) $1800.00 Place Order

Medium Institution - Medium Institution (501 to 2000 users) $2300.00 Place Order

Large Institution - Large Institution (2001+ users) $2500.00 Place Order

For more information please contact:
Standard Reference Data Program
National Institute of Standards and Technology
100 Bureau Dr., Stop 6410
Gaithersburg, MD 20899-6410
(844) 374-0183 (Toll Free) / data [at] (data[at]nist[dot]gov) (E-Mail)

The scientific contact for this database is:
Chris Muzny
Thermodynamics Research Center (TRC)
NIST Applied Chemicals and Materials Division
325 Broadway MS 647.01
Boulder, CO 80305-3337
chris.muzny [at] (chris[dot]muzny[at]nist[dot]gov)
303 497-5549 Phone
Web Address to TRC

Keywords: thermodynamics, thermophysics, recommended data, critically evaluated data, thermophysical properties, TRC, Thermodynamics Research Center

data [at] (Customer Support)

Created August 30, 2010, Updated March 23, 2022