Isotopic compositions of the elements 1981

The Commission's biennial review of isotopic compositions as determined by mass spectrometry has been undertaken by the Subcommittee for the Assessment of Isotopic Composition (SAIC). A critical evaluation of the published literature forms the basis of the Table of Isotopic Compositions and Atomic Weights as Determined by Mass Spectrometry 1981, which is presented here. Atomic Weights calculated from the tabulated isotopic abundances are generally consistent with Asub(r)(E) values in the Table of Standard Atomic Weights 1981 with the most notable exceptions being the elements zinc, germanium and selenium, where the uncertainty intervals just meet or barely overlap. (author)