Development of a compact six-circle goniometer.
A compact versatile six-axis goniometer has been built which can be used with the scattering plane vertical or horizontal for anomalous X-ray diffraction and diffraction X-ray absorption fine structure using a tunable X-ray undulator at SPring-8. The diffractometer consists of a four-circle goniometer for the standard omega, 2theta, phi and chi motions and a two-circle goniometer on the 2theta arm for mounting the detector and analyser crystal. The goniometer is controlled via Ethernet, and standard data-acquisition software with a graphical user interface has been developed. A closed-cycle helium cryostat is mounted on the omega axis for temperature-dependent experiments from 330 K to 14 K. Preliminary experiments on a Bi(2)Sr(2)CaCu(2)O(8) single crystal demonstrate the performance. Superstructure peaks due to the one-dimensional spatial modulations in the b axis were recorded as a function of temperature above 20 K using an image plate.