New capabilities increasing knowledge of heavy element
fate and transport.
BOSTON - Researchers at Pacific Northwest
National Laboratory are uniting theory, computation and experiment to
discover exactly how heavy elements, such as uranium and technetium,
interact in their environment.
As part of that effort, scientists have
combined sensitive experimental measurements with fi rst principle
electronic structure calculations to measure, and to really understand,
the structural and bonding parameters of uranyl, the most common
oxidation state of uranium in systems containing water.
Researchers are discovering how
actinides such as uranium in solution interact with magnetite and
other mineral surfaces.
Image by
Pacific Northwest National Laboratory
The insights were achieved by PNNL scientist
Bert de Jong and associates Gary Groenewold of Idaho National
Laboratory and Michael Van Stipdonk of Wichita State University,
employing the supercomputing resources of the William R. Wiley
Environmental Molecular Sciences Laboratory, a Department of Energy
national scientifi c user facility located at PNNL.
The large number and behavior of electrons in heavy
elements makes most of them extremely diffi cult to study. De Jong
said that advancements in computing power and theory are enabling
computational actinide chemistry to contribute significantly to the
understanding and interpretation of experimental chemistry data, as
well as to predicting the chemical and physical properties of heavy
transition metal, lanthanide and actinide complexes.
�Now we can make sure we get the right answer for
the right reason,� de Jong said, adding that results obtained from the
calculations are an invaluable supplement to current, very expensive
and often hazardous experimental studies.
Researchers are discovering how actinides such as
uranium in solution interact with magnetite and other mineral surfaces.
Discoveries made using the new capabilities
available to the growing field of computational actinide chemistry
could have wide impact, from radioactive waste and cleanup challenges
to the design and operation of future nuclear facilities.
Bert De Jong presented his
work at the 234th American Chemical Society
National Meeting in Boston, Mass., on Sunday, Aug. 19,
2007.
-
PNNL
is a DOE Office of Science national laboratory that solves complex
problems in energy, national security and the environment, and
advances scientifi c frontiers in the chemical, biological,
materials, environmental and computational sciences. PNNL employs
4,200 staff , has a $750 million annual budget, and has been managed
by Ohio-based Battelle since the lab�s inception in 1965.
