Abstract
The traveling solvent floating zone method was applied in growing the single crystals of Bi 2 Sr 2 PrCu 2 O 8+δ . Diffraction patterns of 0kl, 1kl, 2kl, 3kl, 4kl were obtained with the Weissenberg camera equipped with Fuji 400 imaging plate in Photon Factory, KEK. The wavelength of the photon is tuned to IÅ. With this energy, modulation peaks of "order 3" can be recorded clearly. From the extinction conditions in the diffraction pattern indicate the main structure of the crystal can be attributed to orthorhombic Amaa. Using oscillation photograph and zero level Weissenberg photograph, cell lengths of the crystal were calculated to be a = 5.489(2), b = 5.526(5), c = 30.420(7) Å. The crystal possesses an incommensurate modulation along b direction, with modulation wave vector q = 0.243b* + c* and can be expressed as super space group: N 1̄11 Amaa . © 2000 THE PHYSICAL SOCIETY OF THE REPUBLIC OF CHINA.