Mg, Ca and Ba glutaratouranylates – Synthesis and structure

Three novel uranyl coordination polymers were synthesized and structurally characterized by single crystal X-ray diffraction – [Mg(H2O)6][UO2(glt)(Hglt)]2·6H2O (1), [Ca(H2O)4][UO2(glt)(Hglt)]2·4H2O (2) and [Ba(H2O)5][UO2(glt)(Hglt)]2·2H2O (3), where glt = C5H6O4 2− (glutarate) and Hglt...
Ausführliche Beschreibung

Three novel uranyl coordination polymers were synthesized and structurally characterized by single crystal X-ray diffraction – [Mg(H2O)6][UO2(glt)(Hglt)]2·6H2O (1), [Ca(H2O)4][UO2(glt)(Hglt)]2·4H2O (2) and [Ba(H2O)5][UO2(glt)(Hglt)]2·2H2O (3), where glt = C5H6O4 2− (glutarate) and Hglt = C5H7O4 − (hydroglutarate) anions. The structures of compounds 1–3 contain 1D [UO2(glt)(Hglt)]− units that belong to the AQ02B01 (A = UO2 2+, Q02 = glt, B01 = Hglt) crystallochemical group. The different roles of alkaline earth R2+ cations in the structures and the flexibility of the glutarate anions account for the structural distinctions of 1–3. The diverse ways for the connection between the R2+ ions and the [UO2(glt)(Hglt)]− chains, the water content and the geometry of the uranyl-glutarate units present the main structural features of the new complexes. A comparative analysis based on Pauling's second rule of 1–3 and alkali glutaratouranylates has allowed an explanation of their structural dissimilarity. Ausführliche Beschreibung