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1
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9
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15
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1
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9
0
ACKNOWLEDGMENTS
This work was supported by the Director, Office of En-
ergy Research, Office of Basic Energy Science, Chemical
Sciences Division of the U.S. Department of Energy under
Contract No. DE-AC03-76SF00098. The experiments were
conducted at the Advanced Light Source, Lawrence Berke-
ley National Laboratory which is supported by the same
source. Work by S.W.N. and G.E.H. at Brookhaven National
Laboratory was performed under Contract No. DE-AC02-
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