Formation of a uranyl hydroxide hydrateviahydration of [(UO2F2)(H2O)]7·4H2O
| Autor: | Marie C. Kirkegaard, Jennifer L. Niedziela, Michael W. Ambrogio, Andrew Miskowiec, Tyler L. Spano, Brian B. Anderson, Ashley E. Shields |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
010405 organic chemistry
Hydrogen bond Inorganic chemistry Infrared spectroscopy Uranyl fluoride 010402 general chemistry Uranyl 01 natural sciences 0104 chemical sciences Inorganic Chemistry chemistry.chemical_compound symbols.namesake chemistry symbols Uranyl hydroxide Hydrate Raman spectroscopy Schoepite |
| Zdroj: | Dalton Transactions. 48:13685-13698 |
| ISSN: | 1477-9234 1477-9226 |
| DOI: | 10.1039/c9dt02835h |
| Popis: | Hydrated uranyl fluoride, [(UO2F2)(H2O)]7·4H2O, is not stable at elevated water vapor pressure, undergoing a complete loss of fluorine to form a uranyl hydroxide hydrate. Powder X-ray diffraction data of the resultant uranyl hydroxide species is presented for the first time, along with Raman and infrared (IR) spectra. The new uranyl hydroxide species is structurally similar to the layered uranyl hydroxide hydrate minerals schoepite and metaschoepite, but has a significantly expanded interlayer spacing (c = 15.12 vs. 14.73 A), suggesting that additional H2O molecules may be present between the uranyl layers. Comparison of the Raman and IR spectra of this new uranyl hydroxide hydrate and synthetic metaschoepite ([(UO2)4O(OH)6]·5H2O) suggests that the equatorial environment of the uranyl ion may differ and that H2O molecules in the new species participate in stronger hydrogen bonds. In addition, the interlayer spacing of both this new uranyl hydroxide species and synthetic metaschoepite is shown to be sensitive to the environmental humidity, contracting and re-expanding with desiccation and rehydration. Structural distinction between the new uranyl hydroxide species and synthetic metaschoepite is confirmed by a comparison of the thermal behavior; unlike metaschoepite, the new hydrate does not form α-UO2(OH)2 upon dehydration. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|