A new uranyl silicate sheet derived from phosphuranylite topology in the structure of Cs4[(UO2)5(SiO3OH)2O2F4

Abstract

Abstract A new uranyl silicate Cs4[(UO2)5(SiO3OH)2O2F4] (1), was obtained via a hydrothermal route. The new compound is monoclinic, P21/n, a = 8.3870(2), b = 13.4612(2), c = 10.9503(2) Å, β = 91.223(2)°, V = 1236.00(4) Å3; the structure has been solved and refined down to R 1 = 0.022. Therein, the phosphouranylite units ( PU s) associate into a new type of uranyl-silicate layers, [(UO2)5(SiO3OH)2O2F4]4−, which interleave with the Cs+ cations. Topological analysis of PU based structures indicates that these layers in 1 provide a unique example of complexes constructed only via association of the PU and not involving other building units.