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Free SRD

 A catalog of NIST’s free, web interface SRD databases is given below.

SRD 1CNIST Libraries of Peptide Fragmentation Mass Spectra Database

NIST peptide libraries are comprehensive, annotated mass spectral reference collections for various organisms and proteins useful for the rapid matching and identification of acquired tandem mass spectrometry (MS/MS) spectra. Read More
SRD 8NIST XCOM:  Photon Cross Sections Database  

This database can be used to calculate photon cross-sections for scattering, photoelectric absorption and pair production, and total attenuation coefficients, for any element, compound, or mixture (Z ≤ 100), at energies from 1 keV to 100 GeV. Read More
SRD 13NIST–JANAF Thermochemical Tables

This database provides tables of enthalpies (H) and Gibbs energies of formation (G) for more than 1,000 chemical species in solid, liquid, and gas phases. Changes in H and G can be predicted for any reactions among the chemical species. Read More
SRD 17The NIST Chemical Kinetics Database

This database includes essentially all reported kinetics results for thermal gas-phase chemical reactions. The database is designed to be searched for kinetics data based on the specific reactants involved, for reactions resulting in specified products, for all the reactions of a particular species, or for various combinations of these. In addition, the bibliography can be searched by author name or combination of names. The database contains in excess of 38,000 separate reaction records for over 11,700 distinct reactant pairs. These data have been abstracted from over 12,000 papers with literature coverage through early 2000. Read More
SRD 20

NIST X-ray Photoelectron Spectroscopy Database 

This database contains over 33,549 line positions, chemical shifts, doublet splittings, and energy separations of photoelectron and Auger-electron spectral lines, and is searchable by element, line type, line energy, and many other variables. Read More

SRD 30NIST Structural Ceramics Database 

This database provides physical properties for major series of compounds derived from the ceramic oxide, carbide, nitride, boride, and oxynitride chemical families used for structural applications such as heat exchangers and engines. Read more
SRD 40NDRL/NIST Solution Kinetics Database  

This database enables determination of kinetics data on solution-phase reactions through a search form in which reactant(s), product(s), and/or solvent(s) are inputted. Read More
SRD 46

NIST Critically Selected Stability Constants of Metal Complexes

This database provides comprehensive coverage of interactions for aqueous systems of organic and inorganic ligands with protons and various metal ions and is based on the six-volume Critical Stability Constants by Martell and Smith. Read more

SRD 60NIST ITS-90 Thermocouple Database 

This database contains reference functions and tables of thermocouple electromotive force versus temperature for the eight letter-designated thermocouple types: noble-metal types B, R, and S; and base-metal types E, J, K, N, and T. Read More
SRD 62NIST High Temp. Superconducting Materials (HTS) Database 

Thermal, mechanical, and superconducting property data for oxide superconductors, e.g., compounds derived from the Y-Ba-Cu-O, Bi-Sr-Ca-Cu-O, Tl-Sr-Ca-Cu-O, and La-Cu-O chemical families, are provided in this database. Read More
SRD 64NIST Electron Elastic-Scattering Cross-Section Database

This database provides values of differential elastic-scattering, total elastic-scattering, and transport cross-sections for elements with atomic numbers from 1 to 96 needed for quantitative analysis by Auger-electron spectroscopy, X-ray photoelectron spectroscopy, electron microprobe analysis, and analytical electron microscopy. Read More
SRD 66NIST X-ray Form Factor, Attenuation and Scattering Tables

X-ray form factors, attenuation, and scattering tables are widely used in the UV, X-ray and γ-ray communities. In this database, the primary interactions of x-rays with isolated atoms from Z = 1 (hydrogen) to Z = 92 (uranium) are described and computed. Read More
SRD 69NIST Chemistry WebBook

The Chemistry WebBook provides internet access to a variety of physical and chemical property data on well-defined chemical species and reactions. Read More
SRD 71 NIST Electron Inelastic-Mean-Free-Path Database

This database provides values of electron-inelastic mean free paths for elements, inorganic compounds, and organic compounds that are used in quantitative surface analyses by Auger-electron spectroscopy and X-ray photoelectron spectroscopy. Read More
SRD 74NIST Thermodynamics of Enzyme Catalyzed Reactions Database

This SRD contains thermodynamic data for enzyme-catalyzed reactions that are searchable via a novel rule and root based algorithmic method. Read More
SRD 78NIST Atomic Spectra Database

The renowned Atomic Spectra Database contains data for radiative transitions and energy levels in atoms and atomic ions for most of the known chemical elements. Laser Induced Breakdown Spectroscopy data are included. Read More
SRD 81NIST Heat Transmission Properties of Insulating and Building Materials 

Heat transmission properties—thermal conductivity, resistivity, conductance, and resistance—for building materials and thermal insulation are provided in this database. Read More
SRD 82NIST Electron Effective-Attenuation-Length Database

This database provides values of electron-effective attenuation lengths in solid elements and compounds at selected electron energies for surface analysis by Auger-electron spectroscopy and X-ray photoelectron spectroscopy. Read More
SRD 100NIST Database for the Simulation of Electron Spectra for Surface Analysis (SESSA)

SESSA can be used to simulate Auger-electron spectroscopy and X-ray photoelectron spectroscopy spectra of multilayer thin films and nanostructures such as islands, lines, and spheres on surfaces. Read More
SRD 101NIST Computational Chemistry Comparison and Benchmark Database

This database contains experimental and computed (quantum mechanics) thermochemical data for a selected set of nearly 1,900 gas-phase atoms and small molecules. Read More
SRD 106IUPAC/NIST Solubility Data Series

This data, extracted from the IUPAC–NIST Solubility Data Series, contains more than 67,500 entries of mutual solubilities and liquid-liquid equilibria of binary, ternary and quaternary systems. Read More
SRD 107NIST Electron-Impact Cross Section for Ionization and Excitation 

This database provides total ionization cross-sections of molecules by electron impact, cross-sections for some atoms, and energy distributions of ejected electrons for H, He, and H2. Read More
SRD 108NIST Handbook of Basic Atomic Spectroscopic Data

This handbook provides a selection of the most important and frequently used atomic spectroscopic data, including neutral and singly-ionized atoms of the elements hydrogen through einsteinium (Z = 1 to 99). Read More
SRD 111NIST Ground Levels and Ionization Energies for the Neutral Atoms

Ground levels and ionization energies for the neutral atoms are included in this database. Read More
SRD 112NIST Ultraviolet Spectrum of a Platinum Lamp 

The spectrum of a platinum hollow-cathode lamp containing neon carrier gas was recorded photographically and photoelectrically to determine the wavelengths and intensities for about 5600 lines in the region 1130 Å to 4330 Å. Read More
SRD 114NIST Diatomic Spectral Database

This database provides tables of rotational spectral lines for 121 diatomic molecules. The isotopic molecular species, assigned quantum numbers, and observed frequency for each transition are reported, along with derived molecular properties. Read More
SRD 115NIST Hydrocarbon Spectral Database

Rotational spectral lines for 91 hydrocarbon molecules are provided in this database. The isotopic molecular species, assigned quantum numbers, and observed frequency for each transition are reported, along with derived molecular properties. Read More
SRD 116NIST Observed Interstellar Molecular Microwave Transitions Database 

This database provides tabulated transition frequencies for the molecular transitions detected in interstellar and circumstellar clouds and are recommended for reference in future astronomical observations in the cm and mm wavelength regions. Read More
SRD 117NIST Triatomic Spectral Database

Rotational spectral lines for 55 triatomic molecules are provided in this database. The isotopic molecular species, assigned quantum numbers, and observed frequency for each transition are reported, along with derived molecular properties. Read More
SRD 118NIST Wavenumbers for Calibration of IR Spectrometers

The atlas and wavenumber tables in this database consist of spectral maps accompanied by tables of transition wavenumbers and their identity for five molecules: CO, OCS, N2O, NO, and CS2. Read More
SRD 119NIST Photoionization of CO2 (ARPES) Database

This database provides vibrational branching ratios and asymmetry parameters for CO2 determined using synchrotron radiation in the wavelength region of 650 Å to near the ionization onset at about 840 Å. Read More
SRD 120NIST Radionuclide Half-Life Measurements Database

The half-lives of 63 radionuclides measured by NIST are provided in this database. Read More
SRD 121CODATA Internationally Recommended 2014 Values of the Fundamental Physical Constants 

This database reports the CODATA-NIST internationally recommended 2014 values of the Fundamental Physical Constants, and correlation constants between any pair of constants. Read More
SRD 124NIST Stopping-Power & Range Tables for Electrons, Protons, and Helium Ions  

The databases ESTAR, PSTAR, and ASTAR calculate stopping-power and range tables for electrons in any user-specified material and for protons and helium ions in 74 materials. Read More
SRD 126Tables of X-Ray Mass Energy-Absorption Coefficients and Mass Attenuation Coefficients

Tables and graphs of the photon mass attenuation coefficient μ/ρ and the mass energy-absorption coefficient μen/ρ are presented for the elements Z = 1 to 92 and for 48 compounds and mixtures of radiological interest over the photon energy range. Read More
SRD 128NIST X-ray Transition Energies Database

This x-ray transition table provides the energies for K transitions and L transitions for the elements Z = 10 (neon) to Z = 100 (fermium). Read More
SRD 137NIST Fracture Toughness / Fracture Energy Data for Oxide Glass

This database provides values of fracture toughness and fracture energy for borate, germanate, phosphate, and silicate base glasses. Read More
SRD 138NIST Fracture Toughness / Fracture Energy Data for Ceramics 

Fracture toughness and fracture energy values for 52 ceramic materials, including oxides, nitrides, carbides, fluorides, silicon, graphite, and diamond, are provided in this database. Read More
SRD 140NIST Statistical Reference Datasets

This database contains datasets with certified values for assessing the accuracy of software for univariate statistics, linear regression, nonlinear regression, and analysis of variance. Read More
SRD 141NIST Atomic Reference Data for Electronic Structure Calculations

Total energies and orbital eigenvalues for the atoms hydrogen through uranium, as computed in several standard variants of density-functional theory, are presented in this database. Read More
SRD 142NIST Energy Levels of Hydrogen and Deuterium Database

This database provides theoretical values of energy levels of hydrogen and deuterium for principle quantum numbers n = 1 to 200 and all allowed orbital angular momenta l and total angular momenta j. Read More
SRD 147NIST Ionic Liquids Database - ILThermo 

ILThermo is a database of chemical and physical properties of ionic liquids searchable by means of the ions constituting the ionic liquids, the ionic liquids themselves, their properties, and references. Read More
SRD 150NIST Property Data Summaries for Advanced Materials

This database provides physical characteristics (crystallography data, density), mechanical properties (elastic moduli, strength, hardness, toughness, creep, wear), and thermal properties (specific heat, diffusivity, conductivity, expansion) for advanced materials. Read More
SRD 154NIST Backscattering-Correction-Factor Database for Auger Electron Spectroscopy
This database contains values of backscattering correction factors of homogeneous materials for quantitative surface analyses by Auger electron spectroscopy.
Read More
SRD 156NIST Clathrate Hydrate Physical Property Database

Thermodynamic and crystallographic properties of gas hydrates searchable by compound, citation, and property are provided in this database. Read More
SRD 160NIST FLYCHK Modelling Database

FLYCHK provides a suite of models and codes capable of generating atomic level populations and charge state distributions for low-Z to mid-Z elements under non-local thermodynamic equilibrium conditions. Read More
SRD 161NIST Spectrum of Th-Ar Hollow Cathode Lamps 

This atlas presents observations of the spectra of Th-Ar hollow cathode lamps at currents ranging from 20 mA to 320 mA. A list of the spectral lines in each region is included for use as reference wavelengths for the calibration of high-resolution spectrographs. Read more
SRD 164NIST Database of Cross Sections for Inner-Shell Ionization by Electron or Positron Impact

This database provides cross-sections for ionization of the K shell and of the L and M sub-shells in neutral atoms of the elements, from hydrogen to einsteinium, by electron and positron impact. Read More
SRD 165NIST Cell Image Database

This database contains results of controlled cell image experiments on A-10 rat smooth muscle and NIH-3T3 mouse fibroblasts. A novel rule- and root-based method is used to generate experimental metadata. Read More
SRD 166NIST MEMS Calculator

MEMS Calculator determines residual strain, strain gradient, step heights and thicknesses, and in-plane lengths and deflections of thin films from data taken with an optical interferometer or comparable instrument. Read More

SRD 173

NIST Standard Reference Simulation Website

This database provides well-documented simulation results for reliable and well-vetted simulation software for a variety of systems that may be used to validate and test new or existing molecular simulation software. Read More

SRD 204

NIST Polycyclic Aromatic Hydrocarbon Structure Index Database

This database provides the following information for hundreds of polycyclic aromatic hydrocarbon molecules: compound information, 3d models, thermochemistry, and UV-Vis spectra. Read More
SRD 206

Combustion Calorimetry Tool

Combustion calorimetry is the main method for the determination of enthalpies of formation for organic compounds. Read more



































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































Created April 16, 2018, Updated March 1, 2024