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Summary of Minutes of Commission Meeting at IUPAC
General Assembly, Brisbane, Australia, 30 June-2 July 2001
The Commission on Atomic Weights and Isotopic Abundances
(II.1) met for three days of discussions under the chairmanship of
Prof. Ludolf Schultz during the 41st IUPAC General
Assembly in Brisbane. As well as the normal scientific work of Commission
II.1, considerable discussion also took place on the continued existence
of the Commission and the operations of its subcommittees under the
project-driven post-2001 IUPAC.
The standard atomic weights of four chemical elements
have been changed, based on new determinations of isotopic abundances
and reviews of previous isotopic abundances. The standard atomic weight
of zinc was changed from 65.39(2) to 65.409(4), of krypton from 83.80(1)
to 83.798(2), of molybdenum from 95.94(1) to 95.94(2), and of dysprosium
from 162.50(3) to 162.500(1). These changes in atomic weights will
be published in a new Table of Standard Atomic Weights 2001, which
will be submitted to Pure and Applied Chemistry (PAC) by the end of
The Commission also continued its review of publications
on the variation in the natural isotopic abundances in both terrestrial
and extraterrestrial materials. The groundbreaking work of the Subcommittee
for Natural Isotope Fractionation (SNIF) has produced a valuable isotopic
composition database for use by the other subcommittees in determinations
of the uncertainties of atomic weights and culminated in a major manuscript
currently being finalized for publication in PAC.
In the future, the work performed by the SNIF will
be undertaken by the Subcommittee for Isotopic Abundance Measurements.
The element-by-element review 2000 project, coordinated and edited
over the last few years by Prof. John de Laeter, has resulted in a
major document of special historical and scientific interest. This
report is also now being prepared for publication in PAC.
The future of the Commission and its scientific work
was discussed in a joint session with the Commission on Isotopic Specific
Measurements as Traceable References (II.4). The joint session supported
the proposal before the Bureau and Council to establish a Commission
on Isotopic Abundances and Atomic Weights. It was recommended that
the following subcommittees be formed by the Division Committee: Subcommittee
for Isotopic Abundance Measurements (SIAM), Subcommittee for Extraterrestrial
Isotopic Ratios (SETIR), and Subcommittee for Applications of Isotopic
Specific Measurements (SAISR). A number of projects were prepared
by the subcommittees for presentation to the Division Committee.
On a very sad note, the Commission learned of the most
unexpected death of a long-standing Titular Member, Dr. Gregory Ramendik,
in the days immediately following the Commission meeting. Gregorys
efforts on behalf of the Commission will be long remembered, and our
deepest sympathy and condolences are extended to his family and colleagues.
Secretary, IUPAC Commission on Atomic Weights and Isotopic Abundances
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> Summary published in Chem.