The Bernina six-circle surface diffractometer is a standard configuration formed by the XRD combined with the Kappa sample module providing
- 2 detector rotations: gamma, delta
- 4 sample rotations: mu, eta (virtual), chi (virtual), phi (virtual) .
The Kappa module hosts additionally a fully motorized 5 degree of freedom goniometer on top of the sample rotations, three translations (x/y/z) and detachable swivel modules (rx/ry).
Due to beamline design the diffractometer standard position is mirrored compared to most surface diffractomters. The diffractometer angle naming, directions and zeros still follow the popular You-convention, where the chi rotation is at 180° in the standard position.
Pump laser
The surface diffractometer can be combined with essentially all pump laser wavelengths. The pump laser is propagated through air or if required dry Nitrogen purged covers to the sample, but usually bypassing one of the the vacuum or He atmosphere laser incoupling chambers at Bernina.
The Diffractometer frame can be used to support delicate laser setups like e.g. THz focusing elements close to the sample position. As the frame support limits the accessible sample and especially detector angles, the support construction needs to be adapted for each experiment.
Sample mount
Samples on the Surface Diffractometer are typically mounted by either the standard "6mm-pin" designed to fit also the by the 1006 goniometer head from Huber or a standard "10mm-pin" designed to fit the 1003 goniometer head. Drawings of the sample pins can be downloaded from the Sample holders and interfaces page for replication and preparation.