Rietveld quantification of amorphous portions with an internal standard—Mathematical consequences of the experimental approach

摘要: The Rietveld method is increasingly used for amorphous portion determination. This article describes the quantification of portions using an internal standard in a formal mathematical way. From set basic assumptions and postulations, equations quantification, optimum amount standard, slope calculation formula were derived. With this tool set, influence principle on analytical uncertainty discussed. It shown that has strong precision A poor choice can make determination impossible, while clever enhance compared to refinement.