overview

The well-known, high-precision STOE STADI P two circle goniometer is the basis of STOE’s powder diffraction building block system (read more about it here). Vertically or horizontally mounted, the STADI P can be built in Transmission/Debye-Scherrer or Bragg-Brentano geometry. Moreover, two STADI P goniometers, either in the same or different configurations, can be mounted in the same cabinet resulting in two completely independent instruments. However, the two goniometers can also share one source.

• Various single-photon-counting X-ray detectors
• Pure Kα₁ radiation using Co, Cu, Mo and Ag sources
• The ultimate platform for laboratory PDF calculations using Ag Kα₁ data
• Transmission/Debye-Scherrer or Bragg-Brentano mode
• Ideally suited for the analysis of air/moisture-sensitive and microsamples
• A range of high- and low-temperature attachments available

ADVANTAGES OF TRANSMISSION-/ DEBYE-SCHERRER GEOMETRY

• Same sample volume in the beam over the full 2θ scale
• Reliable intensities with no necessity for further mathematical corrections
• No line broadening for weak absorbers
• No height displacement
• Real micro-sampling possible
• Lesser effects of preferred orientation

When an X-ray tube ages, it is possible that its take off angle changes, resulting in a 2 Theta shift of the reflex positions on the detector. To reverse the impact of this take off angle change, the monochromator and sample position have to be adapted through a Beam Optimization.
The STOE STADI P Beam Optimization has been a well-established tool of the WinX^POW software for a very long time. It automatically sets the Johann type monochromator to the maximum intensity of the Ka₁-radiation of a sealed tube’s line focus by the help of a certified standard material – but the alignment of the goniometer axis into the beam path has – so far – still to be done manually with a luminance screen.
From now on, the unique Beam Optimization 2.0 mechanism aligns monochromator and goniometer automated to the Kα₁-radiation, making any contact with the open beam or its air scattered radiation no longer necessary, no matter whether it is only the exchange of a worn-out tube by a new one with the same anode material or whether the radiation should be swapped to a different one.
The STOE Beam Optimization 2.0 is available for all typical anode materials (Co, Cu, Mo, Ag) but currently only for horizontal setups, with plans for future availability in vertical configurations and conveniently, can be integrated into existing horizontal STADI P diffractometers.

As the demand for materials with lower degrees of order continues to rise, the significance of Pair Distribution Function (PDF) measurements is growing steadily. To measure best possible data for PDF interpretation, the STADI P can be installed with Ag Kα₁ radiation and expanded with a PDF collimator, a MYTHEN2 4K detector and optionally air scattering shields, without any loss in diffraction data quality.