Standard Reference Data

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These data are assessed by experts and are trustworthy such that people can use the data with confidence and base significant decisions on the data. NIST provides 49 free SRD databases and 41 fee-based SRD databases. SRD must be compliant with rigorous critical evaluation criteria.聽Send questions to <span class="spamspan"><span class="u">data</span> [at] <span class="d">nist.gov</span></span> or call 1(844) 374-0183聽(Toll聽Free).</p></div> </div> <div class="nist-content-row nist-content-row--width-legible paragraph paragraph--type--text paragraph--view-mode--default"> <div class="nist-block text-long"><h2 class="nist-block__title">Popular Data Products</h2> <p><strong>Recent Update.聽</strong> NIST ICSD SRD3 is currently available, visit聽<a href="https://web.archive.org/web/20231004002911/https://icsd.nist.gov/">https://icsd.nist.gov</a></p> <ul><li><a href="https://web.archive.org/web/20231004002911/https://www.nist.gov/srd/refprop">REFPROP</a>: Reference Fluid Thermodynamic and Transport Properties <em><a href="https://web.archive.org/web/20231004002911/https://pages.nist.gov/REFPROP-docs/">FAQ</a></em></li> <li><a href="https://web.archive.org/web/20231004002911/https://www.nist.gov/srd/nist-standard-reference-database-1a">Mass Spec</a>: NIST/EPA/NIH Mass Spectral Library <a href="https://web.archive.org/web/20231004002911/https://chemdata.nist.gov/dokuwiki/doku.php?id=start">MS Data Center</a></li> <li><a href="https://web.archive.org/web/20231004002911/https://www.nist.gov/srd/nist-standard-reference-database-3">ICSD</a>:聽The NIST Inorganic Crystal Structure Database (ICSD) is聽a comprehensive collection of crystal structure data of inorganic compounds containing more than 210,000 entries and covering the literature from 1913.</li> <li><a href="https://web.archive.org/web/20231004002911/https://trc.nist.gov/tde.html">TDE</a>: NIST ThermoDataEngine聽</li> <li><a href="https://web.archive.org/web/20231004002911/https://www.nist.gov/srd/nist-special-database-33">PIV Cards</a>: NIST Test Personal Identity Verification Card</li> <li><a href="https://web.archive.org/web/20231004002911/https://www.nist.gov/srd/nist-standard-reference-database-31">PED</a>: NIST-ACers Phase Equilibria Diagram Database <a href="https://web.archive.org/web/20231004002911/https://s3.amazonaws.com/nist-srd/ped_demo_5.1_setup_final.zip">5.1聽demo</a>聽and <a href="https://web.archive.org/web/20231004002911/https://pages.nist.gov/PEDEditor/">PED Editor</a></li> <li> <p><a href="https://web.archive.org/web/20231004002911/https://www.nist.gov/srd/nist-standard-reference-database-100">SESSA</a>: NIST Simulation of Electron Spectra for Surface Analysis.聽<span><span><span><strong><span><span><span><span>Now Free!</span></span></span></span></strong></span></span></span></p> </li> <li><a href="https://web.archive.org/web/20231004002911/https://www.nist.gov/srd/srd-catalog/special-databases">Special Databases</a> - <a href="https://web.archive.org/web/20231004002911/https://www.nist.gov/topics/biometrics">Biometrics</a></li> <li><a href="https://web.archive.org/web/20231004002911/https://www.nist.gov/srd/nist-recommended-practice-guide">Selected NIST-Recommended Practice Guides in Material Sciences</a></li> </ul><p>Download <a href="https://web.archive.org/web/20231004002911/https://www.nist.gov/srd/nist-standard-reference-database-100">NIST Simulation of Electron Spectra for Surface Analysis</a>聽<strong>at no cost</strong>.聽聽The <a href="https://web.archive.org/web/20231004002911/https://www.nist.gov/srd/surface-data">surface databases</a> provide data for surface analysis by Auger-electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS). In addition, the NIST Electron Elastic-Scattering Cross-Section Database (SRD 64) and the NIST Database of Cross Sections for Inner-Shell Ionization by Electron or Positron Impact (SRD 164) provide data for Monte Carlo simulations of electron transport in matter and for applications in atomic physics, plasma physics, radiation physics, and materials analysis by electron-probe microanalysis.</p> <h3>SRD Customer Support</h3> <p>100 Bureau Drive, Stop 6410<br> Gaithersburg, MD 20899-6410<br> Tel: 1(844) 374-0183聽(Toll聽Free)<br> e-mail <span class="spamspan"><span class="u">data</span> [at] <span class="d">nist.gov</span></span></p></div> </div> </div> </div> </div> </div> <div class="grid-row"> <div class="nist-resource-block nist-resource-block--first tablet:grid-col"> <div class="nist-resource-block__title-bar"> <div class="nist-resource-block__title"> <div class="nist-resource-block__icon"> <img aria-hidden="true" role="img" alt="decorative icon" 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