PREPARATION AND CRYSTAL STRUCTURES OF DICESIUM BERKELIUM HEXACHLORIDE AND DICESIUM SODIUM BERKELIUM HEXACHLORIDE

Cs2BkCl6 and Cs2NaBkCl6 have been prepared from aqueous solution on the scale of a few micrograms using the isotope 249Bk. The crystal structures of these compounds have been investigated by X-ray powder diffraction. Cs2BkCl6 is not isomorphous with Cs2PuCl6 and Cs2CeCl6, which exhibit trigonal symmetry, but has double the c axis of these compounds, with two molecules per unit cell. The hexagonal lattice parameters (95% confidence) are a = 7.450 (3) Å and c = 12.098 (5) Å. Cs2NaBkCl6 is face-centered cubic and isomorphous with the corresponding americium compound. The lattice parameter is a = 10.805 (3) Å; the crystal contains four molecules per unit cell. © 1969, American Chemical Society. All rights reserved.