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Updated Databases

The NIST Standard Reference Data Group is continuously adding to its sets of evaluated numeric data by updating current databases and developing new databases. The interactive access, available for many products, is also updated on a regular basis.


NIST Standard Reference Database Database 1

NIST 08 includes a fully evaluated collection of electron-ionization mass spectra. It is the product of a 21-year effort by a team of experienced mass spectrometrists in which each spectrum has been examined for correctness. This release contains an expanded MS/MS Library and new Retention Index data.

What's New in v.2.0g distributed with NIST 11

Contents of the NIST/EPA/NIH (NIST 11) Mass Spectral Library
Library Name Library Description Library Contents
mainlib Main EI MS library 212,961 spectra
replib Replicate spectra 30,932 spectra
nist_msms and nist_msms2 MS/MS Library 95,490 spectra of > 16,000 ions
nist_ri Retention Index Library 346,757 Kovats RI values for 70,835 compounds

NIST Standard Reference Database Subscripton Database 1

NIST X-ray Photoelectron Spectroscopy Database: Version 4.0

Version 4.0 of the NIST X-ray Photoelectron Spectroscopy Database contains over 29,000 data records, an increase of 6,844 data records from Version 3.4. For the newly added records, considerable information is supplied about the specimen materials (e.g., specimen morphology and methods of specimen preparation, processing, and characterization), XPS measurement conditions (e.g., type of X-ray source and whether an X-ray monochromator was utilized), and XPS data analysis (e.g., background-subtraction method, peak-location method, and line widths).

The new data records originated from an evaluation of over 5,000 scientific papers that were published generally between 1993 and 1996. Data are given for the positions of photoelectron lines, chemical shifts, doublet splittings, and surface and interface core-level shifts. In addition, data are provided for the kinetic energies of Auger lines measured in an XPS spectrum and for Auger parameters.

NIST Standard Reference Subscription Database 2 Web Thermo Tables (WTT) - Lite Edition

WTT - Lite Edition, a Web version of the TRC Thermodynamic Tables, represents a collection of critically evaluated thermodynamic property data for 150 commonly-used (primarily organic) pure compounds. References to experimental data sources and information and methodology related to the evaluations can be found in these hard-copy publications:

TRC Thermodynamic Tables - HydrocarbonsEditor M. Frenkel National Institute of Standards and Technology Boulder, CO Standard Reference Data Program Publication Series NSRDS-NIST- 75 (1942-2007)Gaithersburg, MDTRC Thermodynamic Tables - Non-HydrocarbonsEditor M. Frenkel National Institute of Standards and Technology Boulder, CO Standard Reference Data Program Publication Series NSRDS-NIST- 74 (1955-2007) Gaithersburg, MD

Various search options based on compound information (empirical formula, partial name, molecular weight) as well as specific property requests are provided. Data presentation features an interactive Web interface with hierarchical expanding/contracting tabular panel structure. Interactive data plotting capabilities are also provided. Unlimited data retrieval and their local storage and use are permitted.

NIST Standard Reference Database 23

Version 9.0 expands the capability of the REFPROP database.

New features include:  

Additional pure fluids and updated equations of state and transport equations, including cyclopentane, R-1234yf, and R-1234ze(E). 

The number of binary mixtures with interaction parameters has increased from 303 to 639, including many mixtures of ethylene, propylene, methanol, ethanol, toluene, benzene, cyclohexane, sulfur dioxide, ammonia, dodecane, acetone, and butylene.

Expanded support for natural gas systems, including the addition of the GERG-2008 mixture model for natural gas fluids, which includes binary interaction parameters for the following fluids: argon, butane, carbon monoxide, carbon dioxide, decane, ethane, helium, heptane, hexane, hydrogen, hydrogen sulfide, isobutane, isopentane, methane, nitrogen, nonane, octane, oxygen, pentane, propane, and water.

Convergence along the saturation lines is now better for complex mixtures due to new algorithms for finding phase boundaries and the addition of analytical derivatives in the calculation of the fugacity. 

Calculation of net and gross heating values for natural gas systems.

Additional pure fluid equations can be loaded in memory that are not included in a selected mixture.  

New plots that show deviations between the GERG-2008 equation and the AGA-8 natural gas mixture models. 


NIST Standard Reference Subscription Database 3 Web Thermo Tables (WTT) - Professional Edition

WTT - Professional Edition, a Web version of the TRC Thermodynamic Tables, represents a complete collection of critically evaluated thermodynamic property data primarily for pure organic compounds. As of September, 2007, WTT contains information on 7765 compounds.  


Created June 14, 2010, Updated June 2, 2021