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GSAS Tutorial - Discussion

Leslie Struble (University of Illinois) and Paul Stutzman (National Institute of Standards and Technology)

Version 1 (March 2015)


It is very easy to get inaccurate quantitative phase analyses using this method even if the fit looks very good and reasonable. Thus validation of results (for example, using chemical composition) is important. For discussion of the accuracy of quantitative phase analysis using this method, see the two International Union of Crystallography (IUCr) Commission reports on round robins [12-13].

Analytical precision and accuracy for cementitious materials are discussed in the ASTM standard [14].

Although only the salicylic acid-methanol and KOH-sugar extraction residues are provided here, HNO3 extraction may also be performed to isolate C4AF and can be very helpful in refining its crystal structure.

Created May 16, 2014, Updated August 25, 2016