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SRD 4 NIST Thermophysical Properties of Hydrocarbon Mixtures Database

SUPERTRAPP is an interactive computer program for predicting thermodynamic and transport properties of pure fluids and fluid mixtures containing up to 20 components.  Read More

NIST 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 20 NIST X-ray Photoelectron Spectroscopy Database 

Starting Friday October 27, XPS will be down for a few weeks for extended maintenance.

This database contains over 22,000 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 35 NIST/EPA Gas-Phase Infrared Database JCAMP Format 

This database contains more than 5200 infrared spectra of different compounds along with chemical structures for most of them.  Read More
SRD 64 NIST 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 66 NIST 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 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 78 NIST 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 82 NIST 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 100 NIST 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 107 NIST 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 108 NIST 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 111 NIST 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 112 NIST 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 114 NIST 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 115 NIST 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 116 NIST 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 117 NIST 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 118 NIST 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 119 NIST 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 120 NIST Radionuclide Half-Life Measurements Database

The half-lives of 63 radionuclides measured by NIST are provided in this database. Read More
SRD 121 CODATA 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 124 NIST 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 126 Tables 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 128 NIST 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 141 NIST 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 142 NIST 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 154 NIST 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 160 NIST 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 161 NIST 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 164 NIST 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


Created August 27, 2010, Updated October 26, 2023