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Online Scientific Databases

AnthroKids - Anthropometric Data of Children displays the results of two studies on anthropometric data of children.

Atlas of the Spectrum of a Platinum/Neon Hollow-Cathode Lamp in the Region 1130-4330 Å contains wavelengths and intensities for about 5600 lines in the region 4330 Å. An atlas plot of the spectrum is given, with the spectral lines marked and their intensities, wavelengths, and classifications listed.

Atomic Energy Levels and Wavelengths References contained in this database are from Bibliography on Atomic Energy Levels and Spectra, NBS Special Publication 363 and Supplements, as well as current references since the last published bibliography collected by the NIST Atomic Spectroscopy Data Center. These references pertain to atomic structure and spectra that arise from interactions or excitations involving electrons in the outer shells of free atoms and atomic ions, or from inner shell excitations corresponding to frequencies up to the soft x-ray range.

Periodic Table: Atomic Properties of the Elements A periodic table, containing NIST critically-evaluated data on atomic properties of the elements [SP 966] was designed as a NIST handout for use at exhibitions and trade shows. The publication of the handout coincided with NIST's centennial celebration in 2001. One side of the handout (shown below) is available online in two formats (PDF & TIFF), and is suitable for high-resolution color printing for desk or wall-chart display. [The other side of the handout (not available online) contains historical information.]

Atomic Reference Data for Electronic Structure Calculations contains total energies and orbital eigenvalues for the atoms hydrogen through uranium, as computed in several standard variants of density-functional theory.

The NIST Atomic Spectra Database (ASD) contains data for radiative transitions and energy levels in atoms and atomic ions. Data are included for observed transitions of 99 elements and energy levels of 52 elements. ASD contains data on about 900 spectra from about 1 Å (Ångströms) to 200 µm (micrometers), with about 70,000 energy levels and 91,000 lines, 40,000 of which have transition probabilities listed. The most current NIST-evaluated data associated with each transition are integrated under a single listing.

Atomic Spectral Line Broadening Bibliographic Database contains approximately 800 recent references, all collected after the last published bibliography. The database contains number data, general information, comments, and review articles.

Atomic Transition Probability Bibliographic Database provides 6,113 references from 1914 through 1999. These papers contain numerical data, comments and review articles on atomic transition probabilities (oscillator strengths, line strengths, or radiactive lifetimes).

Atomic Weights and Isotopic Compositions the atomic weights are available for elements 1 through 111, and isotopic compositions or abundances are given when appropriate.

Bibliography of Photon Total Cross Section (Attenuation Coefficient) Measurements includes papers reporting absolute measurements of photon (XUV, x-ray, gamma-ray, bremsstrahlung) total interaction cross sections or attenuation coefficients for the elements and some compounds.

NIST Biofuel Database brings together structural, biological, and thermodynamic data for enzymes that are either in current use or are being considered for use in the production of biofuels.

The Biological Macromolecule Crystallization Database and NASA Archive for Protein Crystal Growth Data (BMCD) contains the conditions reported for the crystallization of proteins and nucleic acids used in X-ray structure determinations and archives the results of microgravity macromolecule crystallization studies.

The Ceramics WebBook is an gateway to evaluated data, a guide to data centers and sources and a repository for tools and resources for ceramics.

The NIST Chemical Kinetics 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.

The NIST Chemistry WebBook, sixth edition contains thermochemical data for over 6500 organic and small inorganic compounds, reaction thermochemistry data for over 9800 reactions, IR spectra for over 8700 compounds, mass spectra for over 12,600 compounds, UV/Vis spectra for over 400 compounds, electronic / vibrational spectra for over 4100 compounds, constants of diatomic molecules (spectroscopic data) for over 600 compounds, ion energetics data for over 16,000 compounds, and thermophysical property data for 33 fluids. There are many avenues for searching the database.

CIS2 Visual Interoperability Testbed translates a CIS2 file (CIMsteel Integrations Standards) of a steel structure into a 3D interactive model in the form of a VRML (Virtual Reality Modeling Language) file. The translator is part of the research in developing a mapping between VRML prototypes and CIS2.

CKMech Chemical Kinetics Mechanisms was developed to make available data in a report entitled Thermochemical and Chemical Kinetic Data for Fluorinated Hydrocarbons.

The NIST Computational Chemistry Comparison and Benchmark Database is a collection of experimental and ab initio thermochemical properties for a selected set of molecules. Users are provide a benchmark set of molecules for the evaluation of ab initio computational methods and allow the comparison between different ab initio computational methods for the prediction of thermochemical properties.

Dictionary of Algorithms and Data Structures is a dictionary of algorithms, algorithmic techniques, data structures, archetypical problems, and related definitions. Some entries have links to further information and implementations.

The Digital Library of Mathematical Functions (DLMF) is a compendium of essential properties of the special functions of applied mathematics, which are ubiquitous in mathematical modeling and scientific computing. The DLMF includes references to proof sources for every formula, descriptions of relevant mathematical techniques, illustrative graphics , and links to online research literature, algorithms and software. The DLMF is updated periodically to cite or include new published results.

Electron Interactions with Plasma Processing Gases has data excerpted from recently published articles in the Journal of Physical and Chemical Reference Data (JPCRD). Presented here are collision cross section data and electron transport coefficients for gases, such as CF4 and CHF3, used in the manufacturing of semiconductor devices.

The Elemental Data Index provides access to the holdings of the NIST Physics Laboratory online data organized by element. It is intended to simplify the process of retrieving online scientific data for a specific element.

Engineering Statistics Handbook details numerous methods to help scientists and engineers incorporate statistical methods in their work.

Fire Research Information Services (FRIS) is a resource for fire protection engineers, scientists, and fire service personal. It includes FIREDOC which is a complete fire research bibliographic database with 55,000 holdings (published reports, journal articles, conference proceedings, books, and audiovisual items) of FRIS. Each reference has complete bibliographic information.

FLYCHK Collisional-Radiative Code FLYCHK provides a capability to generate atomic level populations and charge state distributions for low-Z to mid-Z elements under NLTE conditions.

Frequencies for Interstellar Molecular Microwave Transitions presents critically evaluated transition frequencies for the molecular transitions detected in interstellar and circumstellar clouds.

CODATA Fundamental Physical Constants, developed in the Physics Laboratory at NIST, addresses three topics: fundamental physical constants, the International System of Units (SI), which is the modern metric system, and expressing the uncertainty of measurement results.

Fundamental Physical Constants - International System of Units (SI) lists important definitions related to the modern metric system of measurement.

Fundamental Physical Constants - Searchable Bibliography on the Constants contains citations for the most important theoretical and experimental publications relevant to the fundamental constants and closely related precision measurements published since the mid 1980s.

Ground Levels and Ionization Energies for the Neutral Atoms provides data for ground state electron configurations and ionization energies for the neutral atoms (Z = 1-104) including references.

The Guide to Available Mathematical Software studies techniques to provide scientists and engineers with improved access to reusable computer software components which are available to them for use in mathematical modeling and statistical analysis. It provides centralized access to such items as abstracts, documentation, and source code of software modules that it catalogs.

Guidelines for Evaluating and Expressing the Uncertainty of NIST Measurement Results presents a method of evaluating and expressing uncertainty in measurement adapted from NIST Technical Note 1297.

NIST Heat Transmission Properties of Insulating and Building Materials provides a valuable reference for building designers, material manufacturers, and researchers in the thermal design of building components and equipment. NIST has accumulated a valuable and comprehensive collection of thermal conductivity data from measurements performed with a 200-mm square guarded-hot-plate apparatus (from 1933 to 1983).

NIST High Temperature Superconducting Materials Database provides evaluated thermal, mechanical, and superconducting property data for oxides and other nonconventional superconductors.

NIST Interactive Algorithm for Isotopic CO2 Measurements is a web-based tool for converting carbon dioxide isotope measurements into standardized delta 13-C and delta-18-O values.

The International Comparisons Database provides information on Appendices B and D of the Comité International des Poid et Mesures (CIPM) Mutual Recognition Arrangement (MRA). The official source of the data is the BIPM key comparison database. The ICDB provides access to results of comparisons of measurements and standards organized by the consultative committees of the CIPM and the Regional Metrology Organizations.

The NIST ITS-90 Thermocouple Database contains the most commonly used tables of NIST Monograph 175, "Temperature-Electromotive Force Reference Functions and Tables for the Letter-Designated Thermocouple Types Based on the ITS-90," by Burns, Kaeser (formerly Scroger), Strouse, Croarkin, and Guthrie. These reference functions have been adopted as standards by the American Society for Testing and Materials and the International Electrotechnical Commission.

The Matrix Market Database is a visual repository of test data for use in comparative studies of algorithms for numerical linear algebra, featuring nearly 500 sparse matrices from a variety of applications, as well as matrix generation tools and services.

NLTE4 Plasma Population Kinetics Database Welcome to the NIST NLTE-4 Plasma Kinetics Modeling Database! This database contains benchmark results for simulation of plasma population kinetics and emission spectra. The data were contributed by the participants of the 4th Non-LTE Code Comparison Workshop who have unrestricted access to the database. The only limitation for other users is in hidden labeling of the output results. Guest users can proceed to the database entry page without entering userid and password.

Phase Diagrams and Computational Thermodynamics - Solder Systems predicts melting temperatures and freezing ranges of lead-free solders which are used to remove lead-containing components from commercial products. This database also shows the effects of non-equilibrium solidification. Also included is a collection of calculated binary and ternary systems that are relevant to solders.

NIST Property Data Summaries for Advanced Materials are topical collections of property values derived from surveys of published data. Thermal, mechanical, structural, and chemical properties are included in the collections.

The Protein Data Bank PDB is the single worldwide repository for the processing and distribution of 3-D biological macromolecular structure data.

It is currently managed by a collaboration of - Rutgers University, Univ. of California - San Diego and NIST.

Radionuclide Half-Life Measurements presents the half-lives of many radionuclides measured at NIST. Revised values for the half lives of various "short-lived" radionuclides arise from improved impurity analysis, incorporation of additional data from new sources, and reevaluation of old data.

NIST Recommended Rest Frequencies for Observed Interstellar Molecular Microwave Transitions -1991 Revision provides critically evaluated transition frequencies for the molecular transitions detected in interstellar and circumstellar clouds. The tabulated transitions are recommended for reference in future astronomical observations in the microwave and millimeter wavelength regions.

SAHA Plasma Population Kinetics Database Welcome to the NIST Saha Plasma Kinetics Modeling Database. This database contains benchmark results for simulation of plasma population kinetics and emission spectra. The data were contributed by the participants of the 3rd Non-LTE Code Comparison Workshop who have unrestricted access to the database. The only limitation for other users is in hidden labeling of the output results. Guest users can proceed to the database entry page without entering userid and password.

Short Tandem Repeat DNA Internet Database is intended to benefit research and application of short tandem repeat DNA markers for human identity testing. Facts and sequence information on each STR system, population data, commonly used multiplex STR systems, PCR primers and conditions and a review of various technologies for analysis of STR alleles have been included.

The Statistical Reference Datasets is also supported by the Standard Reference Data Program. The purpose of this project is to improve the accuracy of statistical software by providing reference datasets with certified computational results that enable the objective evaluation of statistical software.

Stopping-Power and Range Tables for Electrons, Protons & Helium Ions The databases ESTAR, PSTAR, and ASTAR calculate stopping-power and range tables for electrons, protons, or helium ions, according to methods described in ICRU Reports 37 and 49. Stopping-power and range tables can be calculated for electrons in any user-specified material and for protons and helium ions in 74 materials.

NIST Structural Ceramics Database (WebSCD) provides evaluated materials property data for a wide range of advanced ceramics known variously as structural ceramics, engineering ceramics, and fine ceramics.

Tables of X-Ray Mass Attenuation Coefficients and Mass Energy - Absorption Coefficients from 1keV to 20 MeV for Elements Z = 1 to 92 and 48 Additional Substances of Dosimetric Interest include tables covering energies of the photon (x-ray, gamma ray, bremsstrahlung) from 1 keV to 20 MeV.

Thermodynamics of Enzyme-Catalyzed Reactions Database contains thermodynamic data on enzyme-catalyzed reactions that have been recently published in the Journal of Physical and Chemical Reference Data (JPCRD). For each reaction the following information is provided: the reference for the data, the reaction studied, the name of the enzyme used and its Enzyme Commission number, the method of measurement, the data and an evaluation thereof.

ThermoPlan  - NIST Standard Reference Database #167

Experimental Planning and Coverage Evaluation Aid for Thermophysical Property Measurements

This web application provides free and open access for the broader research community to the experimental planning utilities that are incorporated into ThermoData Engine (TDE) [J. Chem. Inf. Model. 2005, 45, 816-838]. TDE provides recommendations for the relative merit of a proposed measurement via assessment of the existing body of knowledge, including availability of experimental thermophysical property data, variable ranges studied, associated uncertainties, state of prediction methods, and parameters for deployment of prediction methods. The web applications provides utilities for the assessment of specific property measurements for pure and binary chemical systems, the broader data needs of pure systems, and recommendations for binary mixture measurements that could extend the current UNIFAC model.



The Database of the Thermophysical Properties of Gases Used in the Semiconductor Industry concerns transport and thermodynamic property data for the gases used in semiconductor processing. The data are useful for equipment modeling in chemical vapor deposition (CVD) processes and the data will also provide a rational basis for the calibration of mass flow controllers (MRCs) used to meter process gases.



The NIST Visible Cement Dataset consists of data on cement pastes with ratios between 0.3 and 0.45 that were prepared and viewed after various hydration times.

Wavenumber Calibration Tables from Heterodyne Frequency Measurements contains the bibliography and atlas as updated through November 1994. The atlas and wavenumber tables consist of many pages of spectral maps accompanied by tables of transition wavenumbers and their identity.

XCOM: Photon Cross Sections Database 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.

X-Ray Attenuation and Absorption for Materials of Dosimetic Interest Tables and graphs of the photon mass attenuation coefficient and the mass energy-absorption coefficient are presented for all of the elements Z = 1 to 92, and for 48 compounds and mixtures of radiological interest. The tables cover energies of the photon (x-ray, gamma ray, bremsstrahlung) from 1 keV to 20 MeV.

X-Ray Form Factor, Attenuation and Scattering Tables this database collects tables and graphs of the form factors, the photoabsorption cross section, and the total attenuation coefficient for any element (Z <=92).

The NIST X-ray Photoelectron Spectroscopy (XPS) Database gives easy access to the energies of many photoelectron and Auger-electron spectral lines. Resulting from a critical evaluation of the published literature, the database contains over 19,000 line positions, chemical shifts, doublet splittings, and energy separations of photoelectron and Auger-electron lines. A highly interactive program allows the user to search by element, line type, line energy, and many other variables.

Created August 30, 2010, Updated August 20, 2018