Neutron diffraction cryo-orienter

The cryo-orienter is used for neutron diffraction studies of single crystals between liquid helium and room temperatures. It combines a double Dewar cryostat with a three-circle goniostat. The temperature of the crystal is controlled by a combination of exchange gas and a bridge circuit to a stability of ±0.01 Kelvin degree. A ring assembly allows the cryostat to be angularly displaced ±50° from vertical (χ), and to be rotated 360° (φ), which provides crystal motion about two axes with ±0.01° precision. The ring assembly can be rotated about the diffraction vector. Crystals can be mounted along a non-major zone and sufficient data can then be collected with one crystal mounting. The ARCADE computer system controls the entire data collection.