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INTRODUCTION
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The way is long and difficult
between the synthesis and the Rietveld refinement when the structure is
unknown :
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One day minimum after recording
good powder data
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Maximum unlimited
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Powder diffraction is not obsolete
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A lot is possible in a "modern"
laboratory equipped with :
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an automatized conventional
X-ray powder diffractometer
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specialized databanks
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unlimited means for calculations
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Aspects of synchrotron and neutron
radiations will be examined too
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A "last chance" method
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The key for success resides
in a very careful work