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Web Thermo Tables


WebThermoTables  delivers the most-up-to-date critically evaluated thermodynamic data, providing a web interface to data from ThermoData Engine.

Features

  • Interactive JS-based web interface with dynamic window-in-window navigation
  • Table generation of model data responsive to user input and specifications
  • Search filters including empirical formula, partial or full name match, molecular weight
  • Unlimited SOURCE queries and local exports of retrieved data sets
  • Detailed description of experiments including bibliographic information, sample specification, and measurement methods
  • Worldwide collection of scientific publications and up-to-date coverage of major publications
TRC-wtt-example

Compound Coverage

WTT Pro

https://wtt-pro.nist.gov
  • Complete collection of critically evaluated property data for tens of thousands of pure organic compounds
  • Without a subscription, access to each compound's WTT Pro data availability 
    (properties provided, ranges of validity, number of experimental data points)

WTT Lite

https://wtt-lite.nist.gov
  • Small subcollection of 150 commonly used, primarily organic pure Compounds
  • Without a subscription, access to each compound's WTT Lite data availability 
    (properties provided, ranges of validity, number of experimental data points)

Licensing

Web Thermo Tables are distributed by

Standard Reference Data Program
National Institute of Standards and Technology
Gaithersburg, MD 20899

Citation Guide

TRC requests that works utilizing WTT include citations.

In-text:

Data provided via the NIST Web Thermo Tables+(SRD 201 or 202 or203) + [version] was used.

Bibliography: depending on version, one of

Liability Statement

This software was developed at the National Institute of Standards and Technology by employees of the Federal Government in the course of their official duties. Pursuant to title 17 Section 105 of the United States Code this software is not subject to copyright protection and is in the public domain. Each of these packages is an experimental system. NIST assumes no responsibility whatsoever for its use by other parties, and makes no guarantees, expressed or implied, about its quality, reliability, or any other characteristic.

Created February 8, 2017, Updated February 18, 2025