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NIST Standard Reference Database 1A
NIST Mass Spectral Libraries, 2026 Edition with Search Program
Data Version: NIST26
Software Version: 4.0
This database is the product of an ongoing comprehensive evaluation and expansion of the world's most widely used mass spectral reference library.
NIST SRD 1A is available ONLY from distributors.
| Contents of the NIST26 Mass Spectral and Retention Index Libraries | ||
|---|---|---|
| NIST/EPA/NIH (EI) Mass Spectral Library | ||
| Tandem (MS/MS) Mass Spectral Library | ||
| GC Method/Retention Index (RI) Library | ||
| Library Description | Library File Name | Library Contents |
| Main EI MS Library | mainlib | 382,180 compounds, 10.1% increase |
| Replicate EI MS Library | replib | 49,095 Alternate spectra of compounds in mainlib, 9% increase |
| HRAM MS/MS Library - small molecules | hr_msms_nist | 2,639,049 Accurate-mass Tandem spectra for 66,782 compounds |
| Low Resolution MS/MS Library - small molecules | lr_msms_nist | 573,673 Low-resolution Tandem spectra for 66,566 compounds |
| APCI High Resolution MS/MS Library - small molecules | apci_msms_nist | 6,403 Accurate-mass Tandem spectra for 623 extractable and leachable compounds
|
| Retention Index Library | nist_ri | 527K RI values for 216K compounds; 188,198 compounds in the Main Library have retention index data. |
Evaluation and Quality Control
- Each spectrum critically examined by experienced mass spectrometrists.
- Each chemical structure examined for correctness and consistency, using both human and computer methods.
- Spectra of all stereoisomers intercompared.
- Chemical names examined by experts and IUPAC names provided.
- Thousands of spectra replaced with higher quality measurements.
- Verified CAS registry numbers.
For more information, please visit:
https://chemdata.nist.gov/
NIST23: Updates to the NIST Tandem and Electron Ionization Spectral Libraries
Electron Ionization Library Component of the NIST/EPA/NIH Mass Spectral Library and NIST GC Retention Index Database
Tandem Mass Spectral Library
The scientific contact for the database is:
Stephen E. Stein
Mass Spectrometry Data Center
National Institute of Standards and Technology
Gaithersburg, MD 20899-8362
(301) 975-2505
massspec [at] nist.gov (massspec[at]nist[dot]gov)
Keywords: analysis; chemical analysis; chemical databases; chemical structure; chemistry; mass spectra; mass spectrometry.