NIST Chemistry WebBook

Version History

June 2005 — present

Incremental improvements added to data collections. See the main page for information on recent changes.

June 2005

• Added gas chromatographic retention database.
• Added the NIST Quantitative IR spectra database.
• Added the NIST THz IR spectra database.
• Added support for the IUPAC international chemical identifier.
• Added the ability to search on a portion of a chemical name.
• Translations into Spanish, Portuguese, French, and Czech, provided courtesy of European Union project "Eurospec - Access to Research Spectroscopic Data and Associated Chemical Knowledge - GTC1-2001-43000"
• Updates provided for many of the datasets previously added to the site.
• Database contents (~70,000 Total species):
  

  Contents of June 2005 release

  Data Type	Number of Species
  Gas phase thermochemical data	6,700+
  Condensed phase thermodynamic data	6,600+
  Phase change thermodynamic data	13,800+
  Reaction thermodynamic data	9,000+
  Gas phase ion energetics data	17,500+
  Gas phase ion cluster data	1,400+
  IR spectrum	16,000+
  THz IR spectrum	33
  Mass spectrum	15,000+
  UV/Vis spectrum	1,600+
  Vibrational & electronic energy levels	5,000+
  Constants of diatomic molecules	600+
  Fluid property data	74
  Gas chromatography data	27,000+

March 2003

• Added group additivity based tool for estimation of gas phase thermochemical properties.
• Added reaction search option.
• Added a large collection of IR spectra.
• Added over 800 UV/Vis spectra.
• Updates provided for many of the datasets previously added to the site.
• Database contents (~48,000 Total species):
  

  Contents of March 2003 release

  Data Type	Number of Species
  Gas phase thermochemical data	6,700+
  Condensed phase thermodynamic data	6,600+
  Phase change thermodynamic data	13,800+
  Reaction thermodynamic data	9,800+
  Gas phase ion energetics data	15,600+
  Gas phase ion cluster data	1,100+
  IR spectrum	16,000+
  Mass spectrum	15,000+
  UV/Vis spectrum	1,600+
  Vibrational & electronic energy levels	4,400+
  Constants of diatomic molecules	600+
  Fluid property data	34

July 2001

• Added limited data from the NIST-TRC source database.
• Added new enthalpy of fusion database.
• Added fluid property models for 17 new fluids.
• Added new capablities to the fluid models including isochors and some transport properties.
• Updates provided for many of the datasets previously added to the site.
• Database contents (~40,000 Total species):
  

  Contents of July 2001 release

  Data Type	Number of Species
  Gas phase thermochemical data	6,500+
  Condensed phase thermodynamic data	5,600+
  Phase change thermodynamic data	13,800+
  Reaction thermodynamic data	9,800+
  Gas phase ion energetics data	15,600+
  Gas phase ion cluster data	1,100+
  IR spectrum	8,700+
  Mass spectrum	12,600+
  UV/Vis spectrum	400+
  Vibrational & electronic energy levels	4,100+
  Constants of diatomic molecules	600+
  Fluid property data	33

February 2000

• Second ion-clustering database added.
• Initial set of 3-d structures added.
• Gas phase heat capacity database added.
• Additonal UV/Vis spectra added.
• Updates provided for many of the datasets previously added to the site.
• Database contents (35,900+ Total species):
  

  Contents of February 2000 release

  Data Type	Number of Species
  Gas phase thermochemical data	6,100+
  Condensed phase thermodynamic data	5,600+
  Phase change thermodynamic data	9,500+
  Reaction thermodynamic data	9,800+
  Gas phase ion energetics data	14,600+
  Gas phase ion cluster data	1,300+
  IR spectrum	7,500+
  Mass spectrum	10,600+
  UV/Vis spectrum	400+
  Vibrational & electronic energy levels	3,800+
  Constants of diatomic molecules	600+
  Fluid property data	16

November 1998

• Additional vibrational enegy levels added.
• Henry's law constant database added.
• UV/Vis spectra added.
• Additional critical property data added.
• Updates provided for many of the datasets previously added to the site.
• Database contents (31,600+ Total species):
  

  Contents of November 1998 release

  Data Type	Number of Species
  Gas phase thermochemical data	6,100+
  Condensed phase thermodynamic data	5,500+
  Phase change thermodynamic data	9,500+
  Reaction thermodynamic data	9,400+
  Gas phase ion energetics data	14,300+
  IR spectrum	7,500+
  Mass spectrum	10,600+
  UV/Vis spectrum	400+
  Vibrational & electronic energy levels	3,300+
  Constants of diatomic molecules	600+
  Fluid property data	16

March 1998

• Vibrational and electronic energy levels for transient polyatomic molecules added.
• Constants of diatomic molecules added.
• Organometallic thermochemistry archive added.
• Updates provided for many of the datasets previously added to the site.
• Database contents (31,600+ Total species):
  

  Contents of March 1998 release

  Data Type	Number of Species
  Gas phase thermochemical data	5,800+
  Condensed phase thermodynamic data	5,300+
  Phase change thermodynamic data	9,400+
  Reaction thermodynamic data	8,700+
  Gas phase ion energetics data	14,300+
  IR spectrum	5,200+
  Mass spectrum	10,600+
  Vibrational & electronic energy levels	2,600+
  Constants of diatomic molecules	600+
  Fluid property data	16

February 1997

• Neutral thermochemistry archive added.
• Condensed phase heat capacity archive added.
• Heat of sublimation database added.
• Boiling point and vapor pressure data added.
• IR and mass spectra added.
• Additional ionization energy and appearance energy data added.
• Proton affinity and gas basicity evaluations added.
• Estimated and uncertain thermodynamic data from NIST Standard Reference Database 19A removed.
• Database contents (22,300+ Total species):
  

  Contents of February 1997 release

  Data Type	Number of Species
  Gas phase thermochemical data	2,800+
  Condensed phase thermodynamic data	4,600+
  Phase change thermodynamic data	7,800+
  Reaction thermodynamic data	4,500+
  Gas phase ion energetics data	12,700+
  IR spectrum	5,200+
  Mass spectrum	8,300+

August 1997

• Fluid property data added.
• Negative ion energetics data added.
• Additional positive ion energetics data added.
• Additional data from the neutral thermochemistry archive added.
• Database contents (27,300+ Total species):
  

  Contents of August 1997 release

  Data Type	Number of Species
  Gas phase thermochemical data	2,800+
  Condensed phase thermodynamic data	4,600+
  Phase change thermodynamic data	8,800+
  Reaction thermodynamic data	7,400+
  Gas phase ion energetics data	14,200+
  IR spectrum	5,200+
  Mass spectrum	8,300+
  Fluid property data	13

August 1996

• First release
• Contains data from NIST Standard Reference Database 19A: NIST Positive Ion Energetics, v. 2.0.
• Database contents (11,000+ total species):

  Contents of August 1996 release

  Data Type	Number of Species
  Thermochemical data and estimates	5,000+
  Gas phase ion energetics data	10,000+