Abstract
High quality diffraction data of high pressure phases of bismuth, Bi III, Bi III' and Bi IV, were obtained by using the high energy Synchrotron Radiation. Based on the observed diffraction data, crystal structures of these phases have been solved as, Bi III : tetragonal structure with unit cell parameters of a=0. 8680 ± 0. 0005 nm and c=0. 4248 ± 0. 0003 nm at 3. 2 GPa, Bi III': the same structure as Bi III, and Bi IV : monoclinic structure with unit cell parameters of a=0. 6463 ± 0. 0005nm, b=0. 6460 ± 0. 0005nm, c=0. 6582 ± 0. 0006 nm and γ=118. 84 ± 0. 05°at 3. 9 GPa and 503 K. The relations of atomic arrangements between Bi III and Bi V, Bu IV and Bi V are discussed.
