The NIST Electron Effective Attenuation Length Database provides values of electron effective attenuation lengths (EALs) in materials at user-selected electron energies between 50 eV and 2,000 eV. The database was designed mainly to provide EALs (to account for effects of elastic-electron scattering) for measurements of the thicknesses of overlayer films and, to a much lesser extent, for measurements of the depths of thin marker layers. EALs are calculated using an algorithm based on electron transport theory for measurement conditions specified by the user. A critical review on the EAL has been published [A. Jablonski and C. J. Powell, Surf. Science Reports 47, 33 (2002)], and simple practical expressions for the EAL, mean escape depth, and information depth are given in another paper by the same authors [J. Vac. Sci. Technol. A 27, 253 (2009)].

The NIST Electron Inelastic-Mean-Free-Path Database provides values of electron inelastic mean free paths (IMFPs) principally for use in surface analysis by Auger-electron spectroscopy and X-ray photoelectron spectroscopy. The database includes IMFPs calculated from experimental optical data and IMFPs measured by elastic-peak electron spectroscopy. If no calculated or measured IMFPs are available for a material of interest, values can be estimated from the predictive IMFP formulae of Tanuma et al. and of Gries. IMFPs are available for electron energies between 50 eV and 10,000 eV although most of the available data are for energies less than 2,000 eV. A critical review of calculated and measured IMFPs has been published [C. J. Powell and A. Jablonski, J. Phys. Chem. Ref. Data 28, 19 (1999)].

Note that this SRD supersedes SRD 64 Version 3.2. The NIST Electron Elastic-Scattering Cross-Section Database provides values of differential elastic-scattering cross sections, total elastic-scattering cross sections, phase shifts, and transport cross sections in electron-atom scattering for elements with atomic numbers from 1 to 96 and for electron energies between 50 eV and 300 keV (in steps of 1 eV). Knowledge of elastic-scattering effects is important for the development of theoretical models for quantitative analysis by Auger-electron spectroscopy, X-ray photoelectron spectroscopy, electron microprobe analysis, and analytical electron microscopy. These data are also needed for modeling of electron transport in radiation dosimetry, electron-beam lithography, and interactions of ionizing radiation with matter. The database is designed to facilitate simulations of electron transport for these and similar applications in which electron energies from 50 eV to 300 keV are utilized. An analysis of available elastic-scattering cross-section data has been published [A. Jablonski, F. Salvat, and C. J. Powell, J. Phys. Chem. Ref. Data 33, 409 (2004)].

**** Note that this SRD is superseded by SRD 64 Version 4.0. ****The NIST Electron Elastic-Scattering Cross-Section Database provides values of differential elastic-scattering cross sections, total elastic-scattering cross sections, phase shifts, and transport cross sections in electron-atom scattering for elements with atomic numbers from 1 to 96 and for electron energies between 50 eV and 300 keV (in steps of 1 eV). Knowledge of elastic-scattering effects is important for the development of theoretical models for quantitative analysis by Auger-electron spectroscopy, X-ray photoelectron spectroscopy, electron microprobe analysis, and analytical electron microscopy. These data are also needed for modeling of electron transport in radiation dosimetry, electron-beam lithography, and interactions of ionizing radiation with matter. The database is designed to facilitate simulations of electron transport for these and similar applications in which electron energies from 50 eV to 300 keV are utilized.An analysis of available elastic-scattering cross-section data has been published [A. Jablonski, F. Salvat, and C. J. Powell, J. Phys. Chem. Ref. Data 33, 409 (2004)].

The NIST Database for the Simulation of Electron Spectra for Surface Analysis (SESSA) can be used to simulate Auger-electron spectra and X-ray photoelectron spectra of nanostructures such as islands, lines, spheres, and layered spheres on surfaces. As for earlier versions, such simulations can be performed for multilayer films. Users can specify the compositions and dimensions of each material in the sample structure as well as the measurement configuration. The database contains extensive physical data needed for quantitative interpretations of observed spectra. A more detailed description of SESSA has been published [W. Smekal, W. S. M. Werner, and C. J. Powell Surf. Interface Anal. 37, 1059 (2005)].

CO2 is studied using dispersed synchrotron radiation in the 650 Å and 840 Å spectral region. The vibrationally resolved photoelectron spectra are analyzed to generate relative vibrational transition amplitudes and the angular asymmetry parameters describing the various transitions observed.

This database collects tables and graphs of the form factors, the photoabsorption cross section, and the total attenuation coefficient for any element (Z <= 92). Version 2.1

A web database is provided which can be used to calculate photon cross sections for scattering, photoelectric absorption and pair production, as well as total attenuation coefficients, for any element, compound or mixture (Z <= 100) at energies from 1 keV to 100 GeV. XCOM provides two forms of output: (a) tables which correspond closely in format to existing tables in the literature; (b) graphical display of the tabular data. Access to the database is provided through a web-based form located at: http://physics.nist.gov/PhysRefData/Xcom/html/xcom1.html.

The NIST Computational Chemistry Comparison and Benchmark Database is a collection of experimental and ab initio thermochemical properties for a selected set of gas-phase molecules. The goals are to provide a benchmark set of experimental data for the evaluation of ab initio computational methods and allow the comparison between different ab initio computational methods for the prediction of gas-phase thermochemical properties. The data files linked to this record are a subset of the experimental data present in the CCCBDB.

The NIST Computational Chemistry Comparison and Benchmark Database is a collection of experimental and ab initio thermochemical properties for a selected set of gas-phase molecules. The goals are to provide a benchmark set of experimental data for the evaluation of ab initio computational methods and allow the comparison between different ab initio computational methods for the prediction of gas-phase thermochemical properties. The data files linked to this record are a subset of the experimental data present in the CCCBDB.