MTDATA – Phase Diagram Software from the National Physical Laboratory









SGSUB: The SGTE Substance Database for use with MTDATA

SGTE LogoThe SGTE Substance Database is developed and maintained by SGTE, a consortium of centres engaged in the development of thermodynamic databases for inorganic and metallurgical systems and their application to practical problems. Please click here for a list of the contents of the database.

The SGTE Pure Substance Database contains data for pure substances and gases. For each substance, the data consist of:

  • the enthalpy of formation at 298.15 K relative to the pure elements

  • the standard entropy at 298.15 K

  • the temperature dependence of the heat capacity typically from 298.15 K (all data at a pressure of 101325 Pa in the NPL implementation)

These data allow the Gibbs energy of each substance to be calculated as a function of temperature and so enable software such as MTDATA to perform phase equilibrium calculations and tabulations.

The present version of the pure substance database (version 12.1) contains assessed thermochemical data for over 4200 substances.

SGORG is an Organic Supplement to the SGTE Pure Substance Database. It contains data for organic species containing more than 3 carbon atoms.

The diagram shows the species formed over a range of temperature for the system 3 C, 8 H, 10 O, 40 N, 0.04 S, 0.02 Na, 0.02 Cl, 0.05 P (in moles), with data taken from the SGSUB and SGORG databases. The calculation involved 72 phases and 457 species.

Calculation for the system C, H, O, N, S, Na, Cl, P from the SGSUB and SGORG databases


Updated 12 June 2009