Synthesis, Crystal Structure and Photoluminescent Properties of a New Uranium-containing Silicotungstate

A new uranium-containing silicotungstate A-beta-Na-14[Na-2(UO2)(2)(SiW9O34)(2)]center dot 43H(2)O (1) was synthesized in an aqueous solution. The compound was characterized by elemental analysis and infrared spectra analysis. A single-crystal X-ray analysis was carried out on crystal (1) which crystallizes in triclinic system, space group p (i) over bar, with a = 13.386 angstrom, b = 13.506 angstrom, c = 16.183 angstrom, alpha = 85.337 degrees, beta = 73.608 degrees gamma = 64.833 degrees and Z = 1. Polyanion (1) consists of two A-beta-SiW9 units which sandwich two uranium and two sodium ions, leading to a Keggin-type sandwich structure. The photoluminescent spectrum of (1) shows typical emission features of uranyl compounds.