Spectroscopic Studies and Crystal Structures of Double Thorium(IV) Oxalates with Sodium Ions

Abstract

Two new double thorium oxalates with sodium ions have been prepared and characterized by using scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDS), Raman spectroscopy and single-crystal X-ray diffraction.

Crystal Growth in the Thorium-TEDGA-Oxalate-Nitrate System: Description and Comparison of the Main Structural Features

“…Their sharing in a bis-bidentate μ 2 -η 2 :η 2 mode between two SBU forms cationic chains, [Th­(TEDGA) 2 (C 2 O 4 )] 2+ ∞ , running along the c axis (Figure c,d). The distance Th–Th through the oxalate ligands is equal to 6.490 Å and is similar to the one encountered in the literature for most of the 10-fold coordinated Thorium­(IV) compounds connected by a bis-bidentate μ 2 -oxalate. , In ( 1 ), the [Th­(TEDGA) 2 (C 2 O 4 )] 2+ ∞ chains are linear with successive Th–Th–Th atoms forming an angle equal to 180°, close to the one found in (NH 4 ) 4 Th­(C 2 O 4 ) 4 ·4H 2 O, while in compounds M 4 [An­(C 2 O 4 ) 4 ]· n H 2 O (An = Th, M = K, N 2 H 5 , n = 4 ; M = C­(NH 2 ) 3 , n = 2; M = Na, n = 5.5 – An = U, M = K, n = 4; M = C­(NH 2 ) 3 , n = 2 and An = Np, Pu, M = C­(NH 2 ) 3 , n = 2) the [An­(C 2 O 4 ) 4 ] 4+ ∞ chains are corrugated with a An–An–An angle close to 158°. − …”

“…These Th–O ether bond values are higher than the mean Th–O oxalate and Th–O carbonyl distances (Table ). The Th–O oxalate distances, between 2.423(7) and 2.509(2)­Å, are similar to those encountered in the literature for μ 2 -η 2 :η 2 and μ 2 -η 2 bridging oxalate ligands. , The Th–O carbonyl bond values are close for compounds ( 1 ), ( 2 ), and ( 4 ). Their values, between 2.421(6) and 2.532(1)­Å, lie within the same range than previously described for carbonyl derivative based compounds. , Unlike Th–O ether , the Th–O carbonyl bond seems affected by the ionic radius variation of Th­(IV) since compound ( 3 ) presents a larger Th–O carbonyl mean distance (2.516(6) Å) than compounds ( 1 ), ( 2 ), and ( 4 ) (2.427(8), 2.460(10), and 2.463(5) Å, respectively).…”

“…The Th−O oxalate distances, between 2.423(7) and 2.509(2)Å, are similar to those encountered in the literature for μ 2 -η 2 :η 2 and μ 2 -η 2 bridging oxalate ligands. 24,42 The Th−O carbonyl bond values are close for compounds (1), (2), and (4). Their values, between 2.421(6) and 2.532(1)Å, lie within the same range than previously described for carbonyl derivative based compounds.…”

From Isolated Molecular Complexes to Extended Networks: Synthesis and Characterization of Thorium Furanmono‐ and Dicarboxylates

“…Beyond the local coordination environment, the 1‐dimensional chains observed in the structures of Th‐1 and Th‐2 are fairly unique within Th(IV) structural chemistry, as only a limited number of related ligand bridged chains have been isolated. Within carboxylate ligand systems, in particular, Th(IV) metal centers linked by oxalate,[7f], glycine,[7e] 2‐sulfobenzoate, pyridinedicarboxylate,[8c] and benzoate[8a] into extended networks have been reported. Notably, the chains vary in overall charge, binding modes of the ligand, and coordination environment about the metal center.…”

“…With respect to the ligand bridged dinuclear species, several oxalate bridged structural units such as that shown in Figure b have been reported. [7f], [26a], [26b], [30c], Relatively fewer dinuclear species, wherein the metal centers are bridged through one tail of the carboxylate (Figure c), are observed. [30b] Moreover, to the best of our knowledge, there is only one other example – a molecular dimer built from the polyamino carboxylic acid DOTA ligand (Figure d)[17c] – in which the Th sites are bridged through the length of the ligand as observed in Th‐3 .…”