A Dinuclear Uranium Complex [{UO2F2(NH3)}2(μ‐F)2]2– from Reaction of TlF and UO2F2 in anhydrous Ammonia and Fluoride Ion Affinities for some Uranyl(VI) Species [UO2F x ]2–xand [UO2F x (NH3)5–x]2–x

Abstract

UO2F2 abstracts F– anions from TlF in liquid ammonia solution and the compound [Tl2(NH3)6][{UO2F2(NH3)}2(μ‐F)2] is formed. The compound has been characterized by single crystal X‐ray diffraction, Raman spectroscopy and quantum‐chemical calculations for the solid state. Quantum‐chemical investigation of the [{UO2F2(NH3)}2(μ‐F)2]2– anion showed that the U–(µ‐F)–U σ‐3c‐4e‐bond is essentially ionic. The [Tl2(NH3)6]2+ cation shows a thallophilic Tl∙∙∙Tl interaction. Fluoride ion affinities (FIAs) were calculated for different UO22+ species [UO2Fx]2–x and [UO2Fx(NH3)5–x]2–x with x = 0 to 4.