Ryoichi Sadanaga

Gas-flame, high-temperature apparatus for single-crystal X-ray diffraction studies

A new high-temperature gas-flame heater utilizing three different kinds of gases has been constructed for single-crystal diffractometry and for photography. The whole system of the heater consists of a burner and gas controller. The temperature control of the heater is carried out by changing the ratio of the flow rates of propane, oxygen and nitrogen gases; the third gas plays a role in increasing blower pressure of the flame and reducing fluctuation of the sample temperature. The heater can thus stably provide a temperature ranging from about 1000°C up to about 2000°C within a deviation of ± 20 °C. The burner has at its end a nozzle head in which Ave holes are so opened that gas flowing through the holes converges to a point 10 mm distant from the head. An accessory device is described which facilitates measuring directly the sample temperatures during the collection of reflection intensities with the single-crystal difTractometer.

The modulated structure of Cu3Bi5S9

The X‐ray diffraction patterns of Cu3Bi5S9 show subsidiary reflections. From these characteristics a model of the modulated structure was uniquely derived. The structure consists of two kinds of slabs: a galena‐like structure and Bi2S4 double chains. The subsidiary reflections are due to a ’’synchronized’’ replacement of Bi atoms within the slab of a galena‐like structure with Cu atoms.