Oxidation of europium with ammonium perfluorocarboxylates in liquid ammonia: pathways to europium(ii) carboxylates and hexanuclear europium(iii) fluoridocarboxylate complexes

Abstract

The novel coordination polymer [Eu(O2CCF3)2(dmf)2]∞ (1) (dmf = N,N-dimethylformamide) containing europium(II) and the two novel compounds (NH4)2[Eu6F8(O2CCF3)12(CF3COOH)6] (2) and (NH4)2[Eu6F8(O2CC2F5)12(C2F5COOH)6]·8C2F5COOH (3), both based on hexanuclear europiate(III) complexes, were synthesized from...

Europium(ii) bis[tetrafluoro-2-(pentafluoroethoxy)ethanesulfonate] – structure and spectroscopic properties of a new near-UV emitter

“…The Eu–O (sulfonate) distances are slightly shorter [average 2.553(28) Å] than in previously published Eu( ii ) ethylenedisulfonate 28 [average 2.584(61) Å] and it may be noticed that they are more uniform than in the cited structure (compare the standard dispersions in the parentheses). On the other hand, the present distances are similar to those reported for the Eu( ii ) trifluoroacetate 44 , [Eu(OCCF 3 ) 2 (dmf) 2 ] ∞ , where the Eu–O (trifluoroacetate) average is 2.553(12) Å. There is a more striking difference between the distances Eu-water in both structures – the average is 2.852 Å in the present structure and 2.690 Å in the Eu ethylenedisulfonate.…”

“…the present distances are similar to those reported for the Eu(II) trifluoroacetate 44 The crystal is held together by weak van der Waals interactions between fluorine atoms belonging to adjacent layers. A view of the crystal packing is shown in Fig.…”

Mixed crystal of bis(ammonium/oxonium) tetraaqua-μ3-fluorido-dodecakis(μ2-trifluoroacetato)octahedro-hexaytterbiate(III) tetrahydrate, [(NH4)1–x (H3O) x ]2[Yb6F8(O2CCF3)12(H2O)4]·4H2O (x = 1/4), containing a hexanuclear ytterbium(III) carboxylate complex with f

“…The Yb-F bond lengths and the bondvalence sums S of 3.01-3.13 valence units give striking struc-tural evidence for the presence of fluorido ligands. Comparisons of the complex anion with the one in the very recent crystal-structure determination of an octahedro-hexanuclear terbium(III) complex containing a [Tb 6 F 8 ] core (Ling et al, 2020) and with some europium(III) complexes containing [Eu 6 F 8 ] cores (Morsbach et al, 2022) reveal that the nonbonding LnÁ Á ÁLn distances [mean 3.97 A ˚(Ln = Tb) and 4.00 A ˚(Ln = Eu)] as well as the Ln-F (mean 2.38 and 2.38 A ˚) and Ln-O bond lengths (mean 2.34 and 2.40 A ˚) in complexes of this type are influenced by the lanthanoid contraction, with these structural parameters decreasing from Eu to Yb due to the smaller ionic radius of Yb III compared to Tb III and Eu III : 1.04 A ˚vs. 1.10 A ˚and 1.12 A ˚(all values for CN 9; Shannon, 1976).…”