Enraf-Nonius Powder Diffraction Systems 120

The laboratory has three Enraf-Nonius Powder Diffraction Systems 120. Rapid data acquisition is achieved by using an INEL 120º curved position sensitive detector (PSD). The set up of each machine varies as follows:

• XRD-PSD2 - Cu Ka₁ radiation - used for phase identification, phase quantification
• XRD-PSD3 - Co Ka1 radiation - used for phase identification, phase quantification, well suited for iron bearing samples
• GeniX High Flux Beam Delivery System - Cu Ka radiation - used with high-temperature stage (Anton Paar HTK10, 20-1600ºC) for monitoring phase transformations and reactions, very small samples possible (micro-to-milligrams, short data collection due to high-flux X-ray source)

Examples for XRD research

Biominerals

• Arctic echinoderms
• Benthic invertebrates from the brackish Baltic Sea
• Geniculate corallines: Providing context for climate change and ocean acidification

Vitrification at high temperatures

• Vitrification of iron age buildings

Dehydration of Na montmorillonite

The basal 001-reflection of the clay mineral Na montmorillonite is shown with progressing dehydration. Loss of interlayer water in Na montmorillonite is accompanied by a stepwise collapse of the clay lattice indicated by sequential appearance of peaks at 18.8 Å (3-water), 14.7-16.0 Å (2-water) and 12.7 Å (1-water).

Change from one state to another is extremely fast and is resolved using short exposure times (one-second X-ray snapshots, GeniX High Flux XRD).