Search

Rare-earth metallic ore in Siping city had produced wastewater containing ytterbium, which has caused certain environmental pollution. In view of the low removal efficiency of ytterbium in wastewater, we developed a novel PAN microtube ultrafilter device with organic P-204 system (UF-OP). The UF-OP had organic P-204 system containing wastewater part with buffer solution acetic acid and enrichment part with nitric acid solution and organic P-204[Di(2-ethylhexyl) phosphoric acid] dissolved in gasoline. Many factors of ytterbium(III) extraction using UF-OP need to explore. The effects of hydrodynamic properties and UF system parameters on the UF-OP process for ytterbium(III) extraction were also studied. The experimental results show that the best extraction conditions of ytterbium(III) were obtained as that nitric acid concentration was 4.00 mol/L, organic P-204 concentration was 0.150 mol/L, and O/W was 0.5 in the enrichment part, and pH value was 4.80 in the wastewater part. Ionic strength of metallic ore wastewater had no obvious effect on ytterbium(III) extraction. When cinit of ytterbium(III) concentration was 1.48 × 10−4 mol/L, the extraction percentage of ytterbium(III) was up to 94.8% in 160 min. The study results would provide theoretical and technical support for the treatment of wastewater containing ytterbium in metallic ore. [ABSTRACT FROM AUTHOR]

The reaction of [Ln(btfa)3(H2O)2] (btfa− = 4,4,4-trifluoro-1-phenyl-1,3-butanedionate) with additional 4,4,4-trifluoro-1-phenyl-1,3-butanedione (Hbtfa) and acridine (Acr) in ethanol allows the isolation of the mononuclear compounds HAcr[Nd(btfa)4]·EtOH, (1) and HAcr[Ln(btfa)4], Ln = Dy (2) and Yb (3); HAcr+ = acridinium cation. Magnetic measurements indicate that complexes 1–3 show field-induced single-ion magnet behavior with anisotropy energy barriers and preexponential factors of Ueff = 20.7 cm−1, τ0 = 24.5 × 10−8 s; Ueff = 40.5 cm−1, τ0 = 8.6 × 10−10 s and Ueff = 22.7 cm−1, τ0 = 8.4 × 10−8 s, for 1–3 respectively. The solid-state luminescence emission in the NIR region shows efficient energy transfer from the 4,4,4-trifluoro-1-phenyl-1,3-butanedionate ligands to the central Ln3+ ion in the case of compounds 1 and 3. [ABSTRACT FROM AUTHOR]

Three new ytterbium complexes of the general formula [YbL2Cl3] with expanded aromatic N‐donor based ligands based on 1,10‐phenanthroline (dipyrido‐[3,2‐f : 2′,3′‐h]‐quinoxaline (DPQ), 2‐methyldipyrido‐[3,2‐f : 2′,3′‐h]‐quinoxaline (MeDPQ) and 1,10‐phenanthroline (Phen)) were synthesized and characterized using different structural analysis, simultaneous thermal analysis, and photoluminescence, and UV‐Vis‐NIR spectroscopy. The compounds were obtained by the reaction of ytterbium(III) chloride hexahydrate and the corresponding aromatic N‐donor through substitution of water from the coordination sphere with the organic ligand. Photoluminescence studies revealed Yb3+‐based NIR emission of the corresponding compounds with following luminescence lifetimes [Yb(DPQ)2Cl3] (1) – 7.8(1) μs, [Yb(MeDPQ)2Cl3] (2) – 9.3(1) μs, [Yb(Phen)2Cl3] (3) – 8.7(1) μs. The resulting complexes are stable under atmospheric conditions, exhibit good thermal stability, and start to oxidize only at sufficiently high temperatures: (1) at 470 °C, (2) at 430 °C, and (3) at 395 °C. [ABSTRACT FROM AUTHOR]

New heterometallic nitrate complexes, namely [Ni(bipy)3][Yb(NO3)5]·0.58MeOH (I), [Ni(phen)3][Yb(NO3)5] (II) and [Ni(phen)3][Yb(NO3)5]·MeOH (II·MeOH), have been prepared and studied. Anions [Yb(NO3)5]2– in these complexes are the first examples of homoleptic ten-coordinatied Yb complexes. The magnetic behavior of single-phase I and II has been studied in static and dynamic modes. A field-induced slowdown of magnetic relaxation, i.e., properties of single-ion magnets (SIMs), was revealed for I and II. Thus, I and II are rare examples of 3d−4f-coordination compounds possessing a discrete structure rather than a joint metal core and demonstrating a slowdown in the relaxation of magnetization. The interplay between the properties of SIM and structural features of I and II was established (CIF CCDC files no. 2103796 (I), 2103797 (II), 2103798 (II·MeOH)). [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Chinese Society of Rare Earths is the property of Editorial Department of Journal of the Chinese Society of Rare Earths and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Metallopolymers based on the Yb(III) complexes with 2-methyl-5-phenyl-1-pentendione-3,5 (mphpd) and allyl-3-oxobutanoate (alacac) were obtained by radical polymerization. The copolymers with methylmethacrylate and styrene in a ratio of 5:95 are obtained. The kinetics of radical polymerization of synthesized metal polymers has been studied. The complexes were characterized by infrared, absorption, diffuse reflectance and fluorescence emission spectra. The spectroscopic studies of the synthesized compounds showed that the configuration of the chelate unit is unchanged during the polymerization. By the luminescent spectroscopy is shown that all studied compounds exhibit effective luminescence. It is established that the luminescence intensity of metalopolymers and copolymers is highest for copolymers and depends on the nature of the ligands. [ABSTRACT FROM AUTHOR]

Synthesis, structure and properties of two alkali-lanthanide heterometallic coordination polymers with the stoichiometric formula [M(OH)(HO)Ln(NO)] (where M is Na and Ln, Er or Yb) are reported. They crystallize in the monoclinic P2/ c space group with very similar cell parameters: a = 15.8777(19) Å, b = 13.4173(18) Å, c = 13.3515(17) Å, β = 93.585(9)º, and V = 2838.8(6) Å for Er(III) and a = 15.8756(5) Å, b = 13.3707(4) Å, c = 13.3083(4) Å, β = 93.584(2)º, and V = 2819.40(15) Å for the Yb(III) polymer. The main findings in the structures of the new compounds are their isomorphism (due to the similarity between erbium and ytterbium ionic radii) and the coexistence in both of highly aqueous coordinated [Na(OH)(HO)] and [Ln(NO)] units. The luminescence measurements in the near infrared region after excitation at different wavelengths have confirmed the deleterious effect (quenching) of OH and HO groups on the emission (intensity and lifetime) of both erbium(III) and ytterbium(III) and the very weak optical absorption of lanthanides. Magnetic measurements show a paramagnetic behavior of the lanthanide centers. Graphical Abstract: Two new isostructural alkali-lanthanide coordination polymers, [Na(OH)(HO)Er(NO)] and [Na(OH)(HO)Yb(NO)], have been synthesized and characterized by X-ray diffraction. Their photoluminescent and magnetic properties are presented.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The (NH)[Yb(ttha)]·5HO ( I) (Httha = triethylenetetramine-N,N,N′,N″,N‴,N‴-hexaacetic acid) and (NH)[Yb(pdta)(HO)]·5HO ( II) (Hpdta = propylenediamine-N,N,N′,N′-tetraacetic acid) complexes are synthesized by heat-refluxing and acidity-adjusting methods, and their structures are determined by single crystal X-ray diffraction techniques. These two complexes are all mononuclear structures. The complex I crystallizes in ttha monoclinic crystal system with the P2/ c space group. The central Yb ion is nine-coordinated only by one the ligand, and one non-coordinate carboxyl group is left. The crystal data are as follows: a = 10.321(4) Å, b = 12.744(5) Å, c = 23.203(9) Å, β = 91.082(6)°, V = 3051(2) Å, Z = 4, D = 1.754 g/cm, μ = 3.150 mm, F(000) = 1636, R = 0.0357, and wR = 0.0672 for 6203 observed reflections with I ≥ 2σ( I). The YbNO part in the [Yb(ttha)] complex anion forms a pseudo-monocapped square antiprismatic polyhedron. The complex II is coordinated with one pdta ligand and two water molecules, which form an eight-coordinate structure, and crystallizes in the triclinic crystal system with the $P\bar 1$ space group. The YbNO part in the [Yb(pdta)(HO)] complex anion makes a pseudo-square antiprismatic polyhedron. The crystal data are as follows: a = 9.8923(9)Å, b = 10.9627(10) Å, c = 12.2618(11) Å, α = 67.284(5)°, β = 70.956(6)°, γ = 68.741(5)°, V = 1115.97(18) Å, Z = 2, D = 1.843 g/cm, μ = 4.264 mm, F(000) = 618, R = 0.0177, and wR = 0.0409 for 4036 observed reflections with I ≥ 2σ( I). [ABSTRACT FROM AUTHOR]

The ytterbium(III) extraction kinetics and mechanism with mixtures of bis(2,4,4-trimethylpentyl)phosphinic acid (Cyanex272) and 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (P507) dissolved in heptane have been investigated by constant interfacial cell with laminar flow. The effects of the stirring rate, temperature, extractant concentration, and pH on the extraction with mixtures of Cyanex272 and P507 have been studied. The results are compared with those of the system with Cyanex272 or P507 alone. It is concluded that the Yb(III) extraction rate is enhanced with mixtures extractant of Cyanex272 and P507 according to their values of the extraction rate constant, which is due to decreasing the activation energy of the mixtures. Atthe same time, the mixtures exhibits no synergistic effects for Y(III), which provides better possibilities for Yb(III) and Y(III) separations at a proper conditions than anyone alone. Moreover, thermodynamic extraction separation Yb(III) and Y(III) by the mixtures has been discussed, which agrees with kinetics results. Extraction rate equations have also been obtained, and through the approximate solutions of the flux equation, diffusion parameters and thickness of the diffusion film have been calculated. [ABSTRACT FROM AUTHOR]

Ytterbium(III) reagent supported on ion exchange resin is applied to the multicomponent condensation reactions under solvent-free conditions. One-pot synthesis of a library of 3,4-dihydropyrimidine-2(1H)-thiones and quinazolin-4(3H)-ones were described. The advantages of easy separation and recyclability of the catalysts were demonstrated. [ABSTRACT FROM AUTHOR]

An 1H, 13C, and 15N NMR study has been completed for the complexes of La(III), Tm(III), and Yb(III) with nitrate and isothiocyanate in aqueous solvent mixtures. Signals for four complexes are observed for both the Tm3+–NO3 − and Yb3+–NO3 − solutions, with the species identified as the mono-, di-, tetra-, and either the penta - or hexanitrato. These results are consistent with those determined for the nitrate complexes of the Ce(III)–Eu(III) metal ions. The chemical shifts for the Tm(III) and Yb(III) nitrate complexes indicate a pseudocontact binding mechanism prevails. The complexes of diamagnetic La(III) with NO3 − produce three signals in the 15NO3 − spectra, with assignments paralleling those observed with the paramagnetic lanthanides. Three complexes are formed in the La3+–NCS− solutions, with signals assigned to the mono-, di-, and triisothiocyanato species. [ABSTRACT FROM AUTHOR]