Unraveling the coordination approach of Eu(iii) in cyphos nitrate ionic liquid – a comprehensive luminescence spectroscopy study

Abstract

In consideration of the mounting attention of the ionic liquid: Cyphos 101 (trihexyl(tetradecyl)phoshonium chloride: [P66614][Cl]) in the recovery of rare earth and other valuables from their waste matrices, an effort...

Synthesis and Characterization of Homoleptic Rare Earth Nitrato Complexes with the Quaternary Ammonium Cations Et4N+ and nPr4N+

“…The synthesis and structural characterization of periodic series of rare earth complexes with halides, pseudo-halides and oxoacids represents a particularly fruitful area for exploration of rare earth chemistry provided the applications of these materials in rare earth separations, recycling, molecular and materials synthesis. These species are utilized in the synthesis of a broad spectrum of rare earth containing molecules and materials, such as emitters in luminescent materials, [5][6][7][8][9][10] anions in functional ionic liquids, [11][12][13][14][15][16][17] and are components of many other compounds with useful magnetic and material properties. [18][19][20][21][22][23][24] When crystallized in the presence of weakly Lewis-acidic cations such as alkali metal cations, trivalent rare earth nitrate salts typically take the form of 10-or 12-coordinate anionic penta-or hexanitrato complexes in the solid state.…”

Understanding the correlation between extraction and luminescence behavior of Eu(iii) in a biphasic system in the presence of Co-extracting metal ions

“…It should be noted that the AR values were evaluated from the intensity ratio (I 615 /I 592 ) of the electric dipole transition to the magnetic dipole transition instead of the area (A 2 /A 1 ) under two peaks, as described 24 These exercises revealed that the solvent extraction results of lanthanides cannot always be correlated with its fluorescence behavior as described elsewhere, and it absolutely depends on the nature of the extractant system and the nature of co-extracting metal ions present along with Ln(III). 26 It has been further clarified with Pd(II)/Eu(III) luminescence results (vide infra). Another reason for the peak intensity enhancement in the presence of Zr(IV) could be ascribed to the co-extraction of NO 3…”

“…FLS-920). 26,27 A fused silica cuvette of 2 mm path length was used for the sample accommodating cell, while a fixed bandpass of 2 nm was employed for the excitation and emission monochromators. For suppressing the scattering effect of the incident beam projected to the monochromator, a long-wavelength pass filter (UV -39, Shimadzu), having a uniform transmittance of 485% above 400 nm, was assimilated ahead of the emission monochromator.…”

“…The increase in the concentration of NO 3 À ion in the extracted phase is known to enhance the peak intensity of the hypersensitive transition ( 5 D 0 -7 F 2 ) of Eu(III) emission. 25,26 Since NO 3 À ion coordinates with Eu(III) in the complex formation, it perturbs the local surroundings of Eu(III) along with the coordinating organic ligands by expelling the inner-sphere water molecules, resulting in an increase in the peak intensity of 5 D 0 -7 F 2 transition. Nevertheless, this presumption can be authenticated only by evaluating the luminescence behavior of Eu(III) in the presence of another fission product, e.g., Pd(II).…”

“…The technique potentially offers an elemental understanding of the metal-ligand complex formation process, and the solvent extraction behavior of a target metal ion can very well be addressed by varying different experimental parameters to evaluate the nature of the metalsolvate species formed in the organic phase under irradiated and unirradiated conditions. 26,27 However, there is no data either through fluorescence or any other spectroscopic techniques on the impact of the co-extracted metal ions on the coordination behavior and nature of the complex formation of Ln(III) ions in a modifierbased extractant system in the context of spent nuclear fuel reprocessing.…”