I  U  P  A  C

News & Notices

Organizations & People

Standing Committees







Links of Interest

Search the Site

Home Page



Current Project

Inorganic Chemistry Division (II)


Number: 2006-025-1-200

Title: Assessment of fundamental understanding of isotopic abundances and atomic weights of the chemical elements

Task Group
Norman E. Holden

Members: John K. Böhlke, Tyler B. Coplen, Paul De Bièvre, John R. de Laeter, and Etienne Roth

Review fundamental issues and concerns that have been raised by members of the Commission on Isotopic Abundances and Atomic Weights (CIAAW). Discuss the issues and present the recommendations to CIAAW on the solution to the problems that will help to provide a future direction for the work of CIAAW on isotopic abundances and atomic weights of the chemical elements.

During the 20th century, the CIAAW evaluated the atomic weights, isotopic abundances and their variations and made recommendations to a general chemical community. This project will evaluate a number of questions that have arisen, and these are posed below.

In the 21st century, are there multiple audiences for the work of the CIAAW? Are Tables of Standard Atomic Weights and of Isotopic Compositions and other data published by CIAAW different for these audiences? Determine details needed in data products that will be published by the CIAAW. Will publication time scales vary for the different groups of audiences? Provide the CIAAW with some recommendations on these issues.

Do the synthetic elements require an atomic weight value and if so, how should this atomic weight be determined?

Does the atomic weight value require a revised definition?

How should the CIAAW treat uncertainties in the recommended values for atomic weights and isotopic abundances? How should the isotopic variations in nature be treated for the various CIAAW audiences? Provide some recommendations to the CIAAW.

Investigate the feasibility for a CIAAW website and web page to market the CIAAW and its activities and provide the latest information to the scientific community on the atomic weights and isotopic abundances. If feasible, web page designs should be provided to CIAAW.

To clarify the isotopic measurement vocabulary, should CIAAW consider preparation of a sub-document of the "ISO" "Vocabulary of Basic and General Concepts in Metrology" (VIM) in the field of isotope measurements as used in many applied scientific fields?


Last update: 8 September 2006

<project announcement published in Chem. Int. Mar-Apr 2007, p. 18>


If you want to update this information, contact us by e-mail
Do not forget to include the Project Number,
your name and relation with that project

Page last modified 16 April 2007.
Copyright ©1997-2007 International Union of Pure and Applied Chemistry.
Questions or comments about IUPAC, please contact, the Secretariat.
Questions regarding the website, please contact Web Help.