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Standard Reference Data

For over 50 years, ֱ has developed and distributed Standard Reference Data in Chemistry, Engineering, Fluids and Condensed Phases, Material Sciences, Mathematical and Computer Sciences and Physics..

New Database

Crystal Structure Database, for more information visit 

ֱ produces the Nation’s Standard Reference Data (SRD). 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. ֱ provides 49 free SRD databases and 41 fee-based SRD databases. SRD must be compliant with rigorous critical evaluation criteria. Send questions to or call 1(844) 374-0183 (Toll Free).

Popular Data Products

Recent Update.  ֱ ICSD SRD3 is currently available, visit 

  • REFPROP: Reference Fluid Thermodynamic and Transport Properties
  • Mass Spec: ֱ/EPA/NIH Mass Spectral Library
  • ICSD: The ֱ Inorganic Crystal Structure Database (ICSD) is a comprehensive collection of crystal structure data of inorganic compounds containing more than 210,000 entries and covering the literature from 1913.
  • : ֱ ThermoDataEngine 
  • PIV Cards: ֱ Test Personal Identity Verification Card
  • PED: ֱ-ACers Phase Equilibria Diagram Database  and
  • SESSA: ֱ Simulation of Electron Spectra for Surface Analysis. Now Free!

  • Special Databases - Biometrics
  • Selected ֱ-Recommended Practice Guides in Material Sciences

Download ֱ Simulation of Electron Spectra for Surface Analysis at no cost.  The surface databases provide data for surface analysis by Auger-electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS). In addition, the ֱ Electron Elastic-Scattering Cross-Section Database (SRD 64) and the ֱ 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.

SRD Customer Support

100 Bureau Drive, Stop 6410
Gaithersburg, MD 20899-6410
Tel: 1(844) 374-0183 (Toll Free)