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NIST Atomic Weights and Isotopic Compositions with Relative Atomic Masses

Metadata Updated: March 14, 2025

The atomic weights are available for elements 1 through 118 and isotopic compositions or abundances are given when appropriate. Version 3.0.

Access & Use Information

Public: This dataset is intended for public access and use. License: See this page for license information.

Downloads & Resources

Dates

Metadata Created Date March 11, 2021
Metadata Updated Date March 14, 2025
Data Update Frequency irregular

Metadata Source

Harvested from NIST

Additional Metadata

Resource Type Dataset
Metadata Created Date March 11, 2021
Metadata Updated Date March 14, 2025
Publisher National Institute of Standards and Technology
Maintainer
Identifier FDB59097467F5200E043065706813E54135
Language en
Data Last Modified 2010-07-01 00:00:00
Category Atomic / molecular / quantum, Physics:Nuclear physics
Public Access Level public
Data Update Frequency irregular
Bureau Code 006:55
Metadata Context https://project-open-data.cio.gov/v1.1/schema/data.json
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id 73283136-7cb2-4811-a26d-8355cc59e6a3
Harvest Source Id 74e175d9-66b3-4323-ac98-e2a90eeb93c0
Harvest Source Title NIST
Homepage URL https://www.nist.gov/pml/atomic-weights-and-isotopic-compositions-relative-atomic-masses
License https://www.nist.gov/open/license
Program Code 006:052
Source Datajson Identifier True
Source Hash 6e83289d4a3afcf45daa7cf9e9a8dc5277f320a0d3ebff4f2b7271a80d252ad6
Source Schema Version 1.1

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