Solid solution quantification from full powder X-ray diffraction profile: novel application of multivariate...

Area of Science:

• Materials Science
• Crystallography
• Analytical Chemistry

Background:

• Non-stoichiometric crystals, like solid solutions, allow property tuning in materials.
• Substitution within crystal structures causes minor cell parameter changes, observable as X-ray diffraction profile shifts.
• The magnitude of the shift correlates with the substitutional amount.

Purpose of the Study:

• To develop rapid quantitative models for solid solution composition using chemometric methods.
• To investigate the efficacy of different X-ray diffraction data alignment strategies.
• To apply these methods to model systems of co-crystals involving nicotinamide, isonicotinamide, fumaric acid, and succinic acid.

Main Methods:

• Utilized chemometric techniques, specifically principal component regression and partial least-squares models.
• Employed X-ray diffraction (XRD) to analyze solid solutions.
• Developed and tested various XRD data alignment strategies.

Main Results:

• Demonstrated the ability of chemometric methods to detect solid solution profile evolution after data alignment.
• Established a correlation between the aligned XRD profiles and the molar composition of the solid solutions.
• Achieved accurate predictions of solid solution composition in test samples.

Conclusions:

• Chemometric analysis of aligned X-ray diffraction data provides a rapid and effective method for quantifying solid solution composition.
• The developed models show high prediction efficacy for co-crystal systems.
• This approach offers a valuable tool for materials characterization and property tuning.