Molybdenum silicide (MoSi₂) is a refractory ceramic and often used in heating elements. In production of MoSi₂, other Mo-Si intermetallic compounds such as Mo₅Si₃ could form. It is important to analyze the purity of MoSi₂ to control the properties of the heating elements. Powder XRD method is suitable to quantify MoSi₂ purity since it can clearly differentiate MoSi₂ from other Mo-Si intermetallic compounds.
The Rietveld analysis is often used as a powder XRD quantitative analysis method but it requires detailed crystal structure information including the atomic positions of all phases in the sample. However, the detailed information might not be always available for the materials you need to analyze. If detailed crystal structure information is not available for the materials you want to analyze, you can use structureless whole powder pattern fitting (WPPF) instead to quantify them.
Figure 1 shows standardless WPPF results of MoSi₂ and Mo₅Si₃ mixture. The data was collected on the MiniFlex 600 with the standard configuration.
Figure 2 shows the result of quantitative analysis. The intensity correction was made using the RIR (reference intensity ratio) values.