Structure de PbU2Se5

PbU₂Se₅ crystallizes in a monoclinic unit cell $\text{a}\text{= 8,605}\text{A}\text{?}$; $\text{b}\text{= 7,788}\text{A}\text{?}$; $\text{c}\text{= 12,27}\text{A}\text{?}$; β = 90° of space group $\text{P}\text{2}{}_1\text{c}$, Z = 4. The crystal structure has been determined for 1251 independant reflections and refined to a final R value of 0,068. Two kinds of uranium sites are found; the average U-Se distances are 2,97 Å for eight-coordination and 2,88 Å in seven-coordination. The average Pb-Se distance for eight-coordination is 3,20 Å. This structure explains the solid solution between PbU₂Se₅ and U₃Se₅.