A hemispherical furnace for high-temperature single crystal X-ray diffraction studies

A high-temperature furnace suitable for single-crystal X-ray diffraction studies has been designed and built. The furnace employs a set of three concentric beryllium hemispheres to provide a vacuum environment for the sample and to act also as a series of heat reflecting shields reducing radiative heat losses. The furnace can be operated from room temperature to at least 1000°C. With a special control circuit, the temperature can be held constant to ± 0.1 °C for extended periods of time. Thermal expansion data have been obtained for β-eucryptite (LiAlSiO₄), beryl (Al₂Be₃Si₆O₁₈) and aluminium titanate (Al₂TiO₅).