Isotopic compositions of the elements 1997

The Commission's Subcommittee for the Isotopic Composition of the Elements (SIAM) has carried out its biennial review of isotopic compositions, as det ermined by mass spectrometry and other relevant methods. This involves a cr itical evaluation of the published literature, element by element, and form s the basis of the Table of Isotopic Compositions of the Elements as Determ ined by Mass Spectrometry presented here. New guidelines have been used to arrive at the uncertainties on the isotopic abundances and there are numero us changes to the Table since it was last published in 1991. Atomic Weights calculated from this table are consistent with (A) under bar(r)(E) values listed in the Table of Standard Atomic Weights 1997.