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#1 Federal
NIST Atomic Weights and Isotopic Compositions with Relative Atomic Masses
- Organization: National Institute of Standards and Technology
- Updated: 2010-07-01 00:00:00
The atomic weights are available for elements 1 through 118 and isotopic compositions or abundances are given when appropriate. Version 3.0.
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Search relevance: 1.00 | Views last month: 3 | Published on: 2025-08-02

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NIST Atomic Weights and Isotopic Compositions with Relative Atomic Masses