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A unit for holding and centring a closed-cycle refrigerator on an Eulerian cradle is described. The X, Y translations orthogonal to the ~0 rotation are obtained by tilting motions, and blocked by a constant springload. Locking is therefore not necessary, and this facilitates the centring of the crystal. In addition, the unit is very easy and cheap to fabricate. The cryostat is in routine operation for neutron diffraction work, and a similar design should be applicable in X-ray diffractometry.

The key technical aspects of the multiple CCD diffractometer CYCLOPS (Cylindrical CCD Laue Octagonal Photo Scintillator) at the Institut Laue–Langevin are described. Laue patterns subtending 270° horizontally by 92° vertically are read out in less than 3 s to allow nearly real time exploration of reciprocal space and rapid data collection through phase transitions. The first experiments on the same thermal beam as OrientExpress have exceeded expectations and promise exciting new applications for neutron Laue diffraction.

Techniques have been developed that allow the measurement of accurate single‐crystal neutron‐diffraction data at pressures up to 10 GPa, using angle‐dispersive methods. High‐quality data have been collected up to 10 GPa, to a resolution of sinθ/λ≃ 1.5 Å−1, from samples of size 3–4 mm. This article presents the methods developed to mount and centre the sample accurately on the instrument; to reduce the background and hence increase the precision of the measured reflection intensities; and to increase further the accessible region of reciprocal space with a single sample loading. Developments are also highlighted, with a view to increasing the range of both science and pressures that can be achieved at the Institut Laue–Langevin reactor source using single‐crystal techniques.

The Fddd four-circle diffractometer system has been developed to perform X-ray diffraction experiments at temperatures as low as 9 K. The diffractometer consists of: (i) a Siemens rotatinganode generator; (ii) a Huber goniometer with offset X circle; (iii) a Siemens Fast Scintillation Detector; and (iv) an APD '202' Displex cryogenic refrigerator. The belt-driven rotating anode gives an X-ray flux that is far in excess of that obtained from a sealed X-ray tube and leads to faster data collections and the opportunity to study smaller samples. X-ray beam alignment requires precise movements of the 300 kg goniometer and this is achieved using compressed air pads. Steel-braided gas lines that allow the transfer of helium gas between the Displex and the compressor are supported by a counterbalance system. The stress on these lines has been reduced by attaching them to the Displex via high-pressure rotating joints and by passing them through a metal ring that is attached to the Z circle. A compact vacuum gauge has been mounted through one of the four ports on the top of the cryostat and gives valuable information on the pressure within the Displex sample chamber during an experiment. Crystals are mounted on sharpened 0.3 mm graphite pencil leads that are held in a newly designed sample mount. The temperature reported from the second stage of the Displex has been assessed by consideration of temperature standards that include the solid-state phase transitions of benzil (1,2-diphenylethanedione) and terbium vanadate.