Uranium(VI) hybrid materials with [(UO2)3(µ3‐O)(µ2‐OH)3]+as the sub–building unit via uranyl–cation interactions

Abstract

AbstractThe hydrothermal reaction of uranyl nitrate with 1,4‐benzenedicarboxylic acid (H2bdc) in the presence of strontium or potassium hydroxides and nitrates afford the formation of two new uranyl hybrid materials featuring extensive uranyl‐strontium or uranyl‐potassium interactions with [(UO2)3(µ3‐O)(µ2‐OH)3]+as the sub‐building unit. Sr1.5[(UO2)12(O)3(OH)13(bdc)4]⋅6H2O (1) contains one‐dimensional (1D) uranyl oxohydroxyl ribbons made of trinuclear pentagonal bipyramidal uranyl units. The ribbons are linked together via uranyl‐strontium interactions to form 2D inorganic domains which are further connected throughµ4‐bdc anions forming a 3D hybrid structure. This is the first reported uranyl‐strontium interaction in extended hybrid solid with the shortest Sr‐O−ylbond length of 2.596 (8) Å. K3[(UO2)12(O)3(OH)13(bdc)4]⋅8H2O (2) has a similar 3D hybrid structure built up through extensive K‐O−ylinteractions with the shortest K‐O−ylbond length of 2.620 (6) Å. Raman spectroscopy has confirmed the presence of oxo‐bridging (U−O−U) vibrations. Thermal stabilities and photoluminescent properties are reported.