Search results for "LANTHANIDE"

Magnetic properties of the layered lanthanide hydroxide series Y(x)Dy(8-x)(OH)20Cl4·6H2O: from single ion magnets to 2D and 3D interaction effects.

2015

The magnetic properties of layered dysprosium hydroxides, both diluted in the diamagnetic yttrium analogous matrix (LYH:0.04Dy), and intercalated with 2,6-naphthalene dicarboxylate anions (LDyH-2,6-NDC), were studied and compared with the recently reported undiluted compound (LDyH = Dy8(OH)20Cl4·6H2O). The Y diluted compound reveals a single-molecule magnet (SMM) behavior of single Dy ions, with two distinct slow relaxation processes of the magnetization at low temperatures associated with the two main types of Dy sites, 8- and 9-fold coordinated. Only one relaxation process is observed in both undiluted LDyH and intercalated compounds as a consequence of dominant ferromagnetic Dy-Dy intera…

Rare earths, zirconium and hafnium distribution in coastal areas: The example of Sabella spallanzanii (Gmelin, 1791)

2016

The Zr, Hf, Y and lanthanide (REE) distribution in biological tissues of Sabella spallanzanii and Styela plicata species collected from two harbours from the northern Sicily is studied for providing information regarding the Zr, Hf and REE uptake from the environment. Previous studies determined the fractionation of dissolved REE scavenged on binding sites onto biological surfaces. By comparing the recognised shale-normalised REE patterns of studied samples with evidence from reference data, the observed behaviour of these elements in biological tissues of Sabella spallanzanii and Styela plicata is interpreted to result from the preferential uptake of intermediate REE onto carboxylic sites.…

Co-crystallization of Keggin type polyoxometalates [HL]3[PW12O40] and [Ln(DMF)8][PW12O40] (Ln=La, Dy, Yb) (L=N-(2-hydroxyphenyl)-3-methoxy-salicylide…

2016

Abstract Four new Keggin type polyoxometalate clusters [HL]3[PW12O40]·5MeOH (1) and [Ln(DMF)8][PW12O40] {Ln = La (2), Dy (3), Yb (4)} (L = N-(2-hydroxyphenyl)-3-methoxy-salicylideneamine) have been synthesized. Co-crystallization of complex 1 with each of the three complexes 2–4 takes place when the Schiff base ligand is treated with hydrated phosphotungstic acid, H3[PW12O40]·xH2O, hydrated lanthanide nitrate, Ln(NO3)3·6H2O in the presence of Ni(NO3)2·6H2O. The Schiff base ligand is protonated in complex 1 and thus it is neutralizing the charge of the polyoxotungstate anion, [PW12O40]3−. A dimethylformamide (DMF) coordinated trivalent lanthanide ion balances the negative charge of the polyo…

Syntheses, characterisation, magnetism and photoluminescence of a homodinuclear Ln(III)-Schiff base family.

2009

A novel family of homodinuclear complexes of the general formula [Ln(2)L(2)(X)(2)] (where Ln = Nd(3+), Pr(3+), Sm(3+) and Tb(3+) for 1, 2, 3 and 4, respectively and X, the coordinated NO(3)(-) or Cl(-) anion) has been synthesised from the corresponding lanthanide(III) salts with the pentadentate dianionic Schiff base ligand, H(2)L [N(1),N(3)-bis(salicylideneimino)diethylenetriamine], that exhibits a N(3)O(2) donor set. Single crystal X-ray diffraction studies evidenced the isostructurality of this family of centrosymmetric neutral dinuclear entities where the Ln(III) metal centres are coupled together by two phenolato oxygen atoms belonging to two units of ligand (H(2)L). Interestingly, the…

ChemInform Abstract: Lanthanide Macrocyclic Complexes: From Molecules to Materials and from Materials to Devices.

2014

In the present review, we show how the chemistry of lanthanide macrocyclic complexes, which began almost 50 years ago in Russia, is still very active. Additionally to bisphthalocyanines complexes, triple-decker, but also quadruple- and quintuple-decker complexes have been synthesized via new chemical routes. The driving force for the development of this chemistry arises from the wide range of possible applications. Owing to their very high conductivity, compared to that of monophthalocyanines, LnPc2 and Ln2Pc3 complexes are used as molecular semiconductors in electronic devices. The radical nature of LnPc2 complexes makes them easily oxidized and reduced. This is the reason why they are par…

Lanthanide macrocyclic complexes: from molecules to materials and from materials to devices

2013

In the present review, we show how the chemistry of lanthanide macrocyclic complexes, which began almost 50 years ago in Russia, is still very active. Additionally to bisphthalocyanines complexes, triple-decker, but also quadruple- and quintuple-decker complexes have been synthesized via new chemical routes. The driving force for the development of this chemistry arises from the wide range of possible applications. Owing to their very high conductivity, compared to that of monophthalocyanines, LnPc2 and Ln2Pc3 complexes are used as molecular semiconductors in electronic devices. The radical nature of LnPc2 complexes makes them easily oxidized and reduced. This is the reason why they are pa…

Modeling the magnetic properties of lanthanide complexes: relationship of the REC parameters with Pauling electronegativity and coordination number

2015

In a previous study, we introduced the Radial Effective Charge (REC) model to study the magnetic properties of lanthanide single ion magnets. Now, we perform an empirical determination of the effective charges (Zi) and radial displacements (Dr) of this model using spectroscopic data. This systematic study allows us to relate Dr and Zi with chemical factors such as the coordination number and the electronegativities of the metal and the donor atoms. This strategy is being used to drastically reduce the number of free parameters in the modeling of the magnetic and spectroscopic properties of f-element complexes. SPINMOL FP7-ERC-247384 ERC-CoG-647301 DECRESIM MAT2011-22785 MAT2014-56143-R CTQ2…

Cover Picture: Dynamic Magnetic and Optical Insight into a High Performance Pentagonal Bipyramidal DyIII Single-Ion Magnet (Chem. Eur. J. 24/2017)

2017

Mononuclear Lanthanide Complexes: Use of the Crystal Field Theory to Design Single-Ion Magnets and Spin Qubits

2015

A SIM-MOF: Three-Dimensional Organisation of Single-Ion Magnets with Anion-Exchange Capabilities

2014

The formation of a metal-organic framework (MOF) with nodes that have single-molecule magnet (SMM) behaviour has been achieved by using mononuclear lanthanoid analogues, also known as single-ion magnets (SIMs), which enormously simplifies the challenging issue of making SMM-MOFs. Here we present a rational design of a family of MOFs, [Ln(bipyNO)4](TfO)3⋅x solvent (Ln=Tb (1); Dy (2); Ho (3); Er (4); TfO=triflate), in which the lanthanoid centres have an square-antiprismatic coordination environment suitable for SIM behaviour. Magnetic measurements confirm the existence of slow magnetic relaxation typical of SMMs, which has been rationalised by means of a radial effective charge model. In add…