Project Details:

Isotopic Abundance Measurements

This subcommittee provides an essential function for the Commission on Atomic Weights and Isotopic Abundances. It collects and evaluates published isotopic abundance data and other information which can influence the tabulated atomic weight of the chemical elements.

This subcommittee has continued to collect and evaluate isotopic abundance data published since 1995. New data on 7 elements was evaluated resulting in a number of changes to the Table of Isotopic Compositions of the Elements. New data on natural isotopic variations was also included. This Table will now be published in 1998, replacing the 1989 version. SIAM did not recommend major changes to the Table of Atomic Weights of the Elements. An internet website is under construction which will allow easy access to data. In the coming 2 years, SIAM will contribute to the activities of the working party of the Commission on Atomic Weights dealing with a revised edition of the element-by-element review.