NIST Atomic Weights and Isotopic Compositions with Relative Atomic Masses

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

Data and Resources

Field Value
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identifier FDB59097467F5200E043065706813E54135
landingPage https://www.nist.gov/pml/atomic-weights-and-isotopic-compositions-relative-atomic-masses
language {en}
license https://www.nist.gov/open/license
modified 2010-07-01
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publisher National Institute of Standards and Technology
resource-type Dataset
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theme {"Atomic / molecular / quantum","Physics:Nuclear physics"}
Groups
  • AmeriGEOSS
  • National Provider
  • North America
Tags
  • amerigeo
  • amerigeoss
  • atomic-mass-evaluation
  • atomic-weights
  • ckan
  • commission-on-atomic-weights-and-isotopic-abundances
  • elemental-data
  • elements
  • geo
  • geoss
  • international-union-for-pure-and-applied-chemistry
  • mass-spectrometry
  • measurements
  • national
  • north-america
  • physics
  • relative-atomic-masses
  • representative-isotopic-compositions
  • siam
  • statistical-evaluation-of-isotopic-abundances
  • subcommittee-for-isotopic-abundance
  • united-states
isopen False
license_id other-license-specified
license_title other-license-specified
maintainer Karen Olsen
maintainer_email karen.olsen@nist.gov
metadata_created 2025-11-19T21:57:17.036450
metadata_modified 2025-11-19T21:57:17.036456
notes The atomic weights are available for elements 1 through 118 and isotopic compositions or abundances are given when appropriate. Version 3.0.
num_resources 1
num_tags 22
title NIST Atomic Weights and Isotopic Compositions with Relative Atomic Masses