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The design of smart nanoplatforms presenting well-definite structures able to achieve controlled cascade action remotely triggered by external stimuli presents a great challenge. We report here a new nanosystem consisting of magnetic iron oxide nanoparticles covalently grafted with a thermosensitive radical initiator alkoxyamine, able to provide controlled and localized release of free radicals triggered by an alternating current (ac) magnetic field. These nanoparticles exhibit a high intrinsic loss power of 4.73 nHm

We report the design of new composite films {Fe[Fe(CN)5(NO)]}0.55@C6H11NO4 and {Ag2[Fe(CN)5(NO)]}0.28@ C6H11NO4 based on cyano-bridged coordination polymers FeII[FeII(CN)5(NO)] or Ag2 I[FeII(CN)5(NO)] grown into a chitosan matrix that are able to provide a slow NO radical release under white light irradiation. The characterisation methods such as X-ray diffraction, TGA, SEM-EDX, IR and UV-vis spectroscopies show that these composites are made of ca. 50 wt% of the cyano-bridged coordination polymer as microcrystalline particles embedded into chitosan films. Irradiation for 7 days by using white light results in initiating a 6.5 and 10.6% NO radical delivery for {Fe[Fe(CN)5(NO)]}0.55@C6H11NO4 and {Ag2[Fe(CN)5(NO)]}0.28@C6H11NO4, respectively. The rearrangement of the cyano-bridged coordination compounds after the NO departure leads to the formation of Prussian blue or silver Prussian blue analogues, which limits the unwanted release of cyanide as a side effect., Institut Carnot Chimie Balard Cirimat, SATT AxLR

This review focuses on recent advances in the post-synthetic modification of nano-sized Prussian blue and its analogues and compares them with the current strategies used in metal–organic frameworks to give future outlooks in this field.

Erbium(iii) complexes based on halogenated ligands.

International audience; We report here the synthesis, structure, luminescence, and magnetic properties of three new cage-like tetranuclear silsesquioxanes (Et 4 N) 2 [(PhSiO 1..5) 8 (Y 0.75 Dy 0.25 O 1.5) 4 (O)(NO 2.5) 6 (EtOH) 2 (MeCN) 2 ] and (Cat) 2 [(PhSiO 1.5) 8 (DyO 1.5) 4 (O)(NO 2.5) 6 (EtOH) 2 (MeCN) 2 ] (Cat=Et 4 N or Ph 4 P). They present a characteristic greenyellow emission. The Y 3+ /Dy 3+ compound displays in addition a field-induced Single Molecule Magnet (SMM) behavior making it the first reported bifunctional magneto-luminescent silsesquioxane.

We report in this article new magneto-plasmonic core@satellite Prussian Blue Analogue (PBA)@Au-Ag nanoheterostructures obtained by post-synthetic adsorption of a bimetallic [AuI2AgI2(C6F5)4(OEt2)2]n molecular complex with ferromagnetic K+/Ni2+/[Cr(CN)6]3- PBA nanoparticles. While the size, shape and structural integrity of the PBA nanoparticles are preserved upon the formation of the core@satellite heterostructures, a dramatic change in the magnetic properties is observed due to the presence of ultrasmall gold-silver nanosatellites. Moreover, the nanoarchitectures behave also as multicatalysts towards the reduction of 4-nitrophenol with enhanced activity as compared to the pristine K+/Ni2+/[Cr(CN)6]3- PBA. Remarkably, these performances are found to be heightened upon light irradiation due to a plasmon-assisted catalytic effect. Such original PBA core@Au-Ag satellite architectures constitute a rare example in which an interplay between the two constituting materials leads to a reshaping of the magnetic and catalytic features.

We report the synthesis and structures of three luminescent dysprosium(iii) complexes based on fluorinated alkoxide ligands of formulas [Dy(L1)2(THF)4][BPh4]·0.5THF (1), [Dy(L2)2(THF)5][BPh4]·2.5THF (2) and [Dy(L3)2(THF)5][BPh4]·2THF (3) (L1 = (CF3)3CO-, L2 = C6F5C6F4O-, L3 = C6F5C(CH3)O-). Despite the different dysprosium ion geometries (octahedral vs. distorted pentagonal bipyramidal), these systems exhibit a single-molecule magnet (SMM) behavior, but with distinct relaxation dynamics. Moreover, a typical dysprosium-based luminescence is observed for the three complexes, which make them bifunctional magneto-luminescent SMMs. Remarkably, complex 3 exhibits a high anisotropy barrier of 1469 cm-1 and a blocking temperature of 22 K, making it one of the most performant alkoxide-based SMMs with the highest blocking temperature for a luminescent SMM.

We report the synthesis, structures, and magnetic investigations of two new octahedral dysprosium complexes, based on the original N-heterocyclic carbene (NHC) tridentate bis(phenoxide) ligand, of the respective formulas

We investigated a series of Mn

New luminescent cage-like tetranuclear silsesquioxanes [NEt

International audience; We report here two dysprosium complexes based on phenoxidebased emissive ligands 1-(2,4-dimetylphenylazo)-2-naphtholate (L1) and anthracenolate (L2). While 1 is a dinuclear homoleptic complex [Dy 2 (L1) 6 ]•2C 7 H 8 exhibiting a zero-field slow relaxation of the magnetization, 2 is a mononuclear complex [Dy(L2) 3 (py) 3 ] (py = pyridine) showing a field-induced relaxation.

Five neutral bis(μ-phenoxido)dicopper(II) complexes, [Cu2(LMe,Me,Me)2] (1), [Cu2(LMe,Me,Et)2]·CH2Cl2 (2), [Cu2(Li-Pr,i-Pr,i-Pr)2]·2H2O (3), [Cu2(Lt-Bu,Me,i-Pr)2] (4), and [Cu2(Lt-Bu,t-Bu,i-Pr)2]·H2O (5) have been synthesized and characterized by single-crystal X-ray diffraction analyses, magnetic studies, and density functional theory (DFT) calculations, in which the ligands [H2LMe,Me,Me = N,N-bis(2-hydroxy-3,5-dimethylbenzyl)-N′,N′-dimethylethylene-1,2-diamine, H2LMe,Me,Et = N,N-bis(2-hydroxy-3,5-dimethylbenzyl)-N′,N′-dimethylethylene-1,2-diamine, H2Li-Pr,i-Pr,i-Pr = N,N-bis(2-hydroxy-3,5-diisopropylbenzyl)-N′,N′-diisopropylethylene-1,2-diamine, H2Lt-Bu,Me,i-Pr = N,N-bis(2-hydroxy-3-tert-butyl-5-methylbenzyl)-N′,N′-diisopropylethylene-1,2-diamine, and H2Lt-Bu,t-Bu,i-Pr = N,N-bis(2-hydroxy-3,5-di-tert-butylbenzyl)-N′,N′-diisopropylethylene-1,2-diamine] contain the same [O,N,N,O]-donor atoms combination but differ in substituents at phenol rings and at an amino nitrogen atom. The effect of these remote substituents on the nature of exchange coupling interactions (ferromagnetic vs antiferromagnetic) between the copper(II) ions has been investigated. The average Cu–O–Cu angle, Cu–O–Cu–O torsion angle, and Cu···Cu separation in 1–5 are varied systematically by these remote ligand substituents in the range 98.6–83.3°, 26.0–46.5°, and 2.982–2.633 Å, respectively. As a result, the intramolecular spin–spin coupling in these complexes are changing gradually from a strong antiferromagnetic (J = −395 cm–1, where Ĥ = −JŜ1Ŝ2) to a moderate ferromagnetic (J = +53.2 cm–1) regime. The crossover angle at which the magnetic interaction changes from antiferromagnetic to ferromagnetic (J = 0) is determined to be ca. 87° for this series of dicopper(II) complexes. DFT calculations support the experimentally determined crossover angle and disclose various magneto–structural correlations in the series 1–5.

International audience; We report here the synthesis, structure, magnetic and photoluminescence properties of three new bifunctional Schiff-base complexes [Dy(L1)2(py)2][B(Ph)4]•py (1), [Dy(L1)2Cl(DME)]•0.5DME (2) and [Dy(L2)2Cl]•2.5(C7H8) (3) (HL1 = Phenol, 2,4-bis(1,1dimethylethyl)-6-[[(2-methoxy-5-methylphenyl)imino]methyl]; HL2 = Phenol, 2,4-bis(1,1-dimethylethyl)-6-[[(2-methoxyphenyl)imino] methyl]). The coordination environment of the Dy 3+ ion and the direction of the anisotropic axis may be controlled by the combination of the substituent groups of the Schiff bases, the nature of the counter-ions (Cl  vs. BPh4 ) and the coordinative solvent molecules. A zero-field slow relaxation of the magnetization is evidenced for all complexes but strong differences in the relaxation dynamics are observed depending on the Dy 3+ site geometry. In this sense, complex 1 exhibits an anisotropic barrier of 472 cm 1 , which may be favourably compared to other related examples due to the shortening of the Dy-O bond in the axial direction. Besides, the three complexes exhibit a ligand-based luminescence making them as bifunctional magneto-luminescent systems.

International audience; We report in this communication the synthesis, structure and magnetic investigations of two new half-sandwich complexes [Dy(DAD)Cp*(THF)] (1) and [Li(THF) 3 ][Dy(DAD)Cp*Cl] (2) (Cp* = C 5 Me 5 , DAD = [2,6-iPr 2 C 6 H 3 N-CMeCMe-NC 6 H 3 iPr2-2,6). Both compounds exhibit zero-field SMM behavior but distinct relaxation dynamics originating from difference in the arrangement of Cp* and DAD ligands. The anisotropic barrier for 1 is found one order of magnitude greater than for 2.

International audience; We report the synthesis and magnetic investigation of a dysprosium pentagonal bipyramidal complex [Dy(THF)5Cl2][BPh4] (1) exhibiting a linear Cl–Dy–Cl sequence suitable for providing a coordination environment allowing a zero-field slow relaxation of the magnetization. Besides, the complex also shows dual luminescence originating from [BPh4]− and Dy3+.

International audience; Materials developed for radionuclide adsorption need to resist harsh conditions, i.e. be robust against ionizing radiation. In this work, we evaluated the degradation of mesoporous silicas (SBA-15) grafted with hydroxypiridinone, acetamide phosphonate and propionamide phosphonate ligands under electron irradiation. The ligands contained amide and phosphinic acid functional groups, which made them able to bind to actinides. Degradation of the grafted ligand was assessed by identifying and quantifying the gas produced under irradiation using gas chromatography, as well as characterizing the grafted ligands before and after irradiation by means of FT-IR, XPS and TGA techniques. Irradiation led to the degradation of amide functional groups and to the production of amine and carboxylic acid groups. Corresponding reaction mechanisms are proposed. The sorption behavior of the grafted SBA-15 materials for thorium was also studied. SBA-15 materials grafted with acetamide phosphonate and propionamide phosphonate ligands were shown to be able to adsorb thorium. The propionamide phosphate ligand was the most efficient, with an equilibrium sorption capacity of 95 mg g$^{−1}$. This capacity remains stable up to a 1 MGy irradiation dose and undergoes a 20% decrease after 4 MGy of irradiation. Therefore, this material is potentially interesting for the treatment of liquid outflows contaminated by actinides produced in nuclear facilities.

International audience; We report the synthesis, magnetic and photoluminescence investigations of two bifunctional dysprosium complexes based on tridentate Schiff base ligands. Magnetic investigations reveal a genuine Single-Molecule Magnet (SMM) behavior with out-of-phase signals up to 60 K, and the tunable emission arising from the Schiff base ligands.

A series of dinuclear lanthanide complexes incorporating the 2-ethoxycinnamate ligand have been synthesized and characterized using elemental analyses, infra-red spectroscopy, X-ray diffraction and magnetic measurements. Depending on the nature of the lanthanide ion, three different isostructural series of respective formulas, [Ln(L)3(DMSO)(H2O)]2 (Ln = Ce (1), Nd (2)), [Ln(L)3(DMSO)x(DMF)y(H2O)]2 (Ln = Gd (3), Dy (5) and Er (6)) and [Tb(L)3(DMF)(H2O)]2 (4) have been obtained. Investigations of their magnetic properties reveal a genuine single-molecule magnet behaviour observed for the dysprosium based compound 5, while a field-induced slow relaxation of the magnetization is found for compounds 1, 2 and 3.

International audience

We report a new approach for the synthesis of multifunctional Au core@Prussian Blue analogous (PBA) shell nanoheterostructures that involves PBA shell growth on the surface of cyanide-stabilized gold nanoparticles. It permits the assembly of Au@KNiII[FeII(CN)6] core@shell and Au@KNiII[FeII(CN)6]@KNiII[CrIII(CN)6] core@shell@shell heterostructures with well-defined and size-controlled gold cores and PBA shells. These heterostructures exhibit tunable size- and shape-dependent magnetic and optical properties: (i) the surface plasmon resonance band position and intensity mainly depend on the PBA shell thickness, and (ii) the magnetic properties (the transition temperature, the coercivity, and magnetic regime) depend in a complex manner on the thickness as well as the particular morphology of the magnetic shell.

We report an investigation on the synthesis, structure and magnetic properties of a series of heteroleptic Zn

Discovery of novel compounds capable of electrochemical ion intercalation is a primary step toward development of advanced electrochemical devices such as batteries. Although cyano-bridged coordination polymers including Prussian blue analogues have been intensively investigated as ion intercalation materials, the solid-state electrochemistry of the octacyanotungstate-bridged coordination polymer has not been investigated. Here, we demonstrate that an octacyanotungstate-bridged coordination polymer Tb(H2O)5[W(CN)8] operates as a Li(+)-ion intercalation electrode material. The detailed magnetic measurements reveal that the tunable amount of intercalated Li(+) ion in the solid-state redox reaction between paramagnetic [W(V)(CN)8](3-) and diamagnetic [W(IV)(CN)8](4-) in the framework enables the electrochemical control of different magnetic regimes. While the initial ferromagnetic long-range ordering is irreversibly lost upon lithium insertion, electrochemical switching between paramagnetic and short-range ordering regimes can be achieved.

We report here the synthesis and investigation into the magnetic properties of a luminescent trinuclear Zn

Access to multifunctionality at the nanoscale requires the development of hybrid nanostructures that combine materials of different natures. In this line of thought, current research on coordination polymers is not only focusing on their synthesis at the nanoscale, but also on combining these polymers with other materials. According to a novel and rational approach, single-layer Au@Prussian blue analogue (PBA) and double-layer Au@PBA@PBA' core-shell nanoparticles (NPs) may be obtained through the growth of a cyano-bridged coordination network on the gold surface. The nanosized heterostructures combine the plasmonic optical properties of the gold core and the magnetic properties of the PBA shell. Whereas the single-layer nanoparticles are paramagnetic, the double-layer nanostructures display ferromagnetism; therefore, the overall structural motif may be considered as multifunctional. The developed synthetic concept also includes an easy access to hollow PBA NPs.

An original approach to immobilize ruthenium species and then transform them into RuO2 nanoparticles is presented that uses hybrid-functionalized glasses. First, different chemical graftings of functional groups (acetylacetonate, amine, nitrile, pyridine and thiol) in porous glass were used to extract ruthenium-containing complexes ([Ru(CH3N)4Cl2] and Ru(NO)(NO3)3) from solutions. The best functional groups to selectively coordinate Ru complexes and thus extract it from the solutions have been determined. Then, the obtained Ru-containing composite glass was heated under air to remove the organic species and to obtain RuO2 nanoparticles inside a glass with centimetre scale geometric form. The as-obtained materials were studied by transmission electron microscopy (TEM), scanning electron microscopy (SEM), nitrogen physisorbtion measurements, elemental analysis and X-ray diffraction (XRD).

A new exploit of ionic liquids as an alternative reaction media in the synthesis of cyano-bridged coordination polymers nano-objects such as nanoparticles and their superstructures is discussed. Stable colloidal solutions containing nanoparticles of cyano-bridged coordination polymers Cu 3 [Fe(CN) 6 ] 2 /[C n -MIM][An] (where n = 2, 4; An = BF 4 , Cl) or their superstructures were prepared in the corresponding 1-R-3-methylimidazolium salts [C n -MIM][An] which acts as both the stabilizing agent and the solvent. Different conditions, such as temperature, nature of the ionic liquid counter anion and N -alkyl substituted chain length, water content and microwave action have been varied in order to check their influence on the size, the shape and the organisation of the nanoparticles. A special emphasis is devoted to detailed studies of the magnetic properties of these frozen colloids. The dynamic study shows that the relaxation of magnetisation for the nanoparticles and their superstructures is influenced by interparticle interactions leading to appearance of a cluster-glass-like behaviour in these systems.

Quantum chemistry calculations of CASSCF/CASPT2 level together with ligand field analysis are used for the investigation of magnetic anisotropy of [Mo(CN)7]4- complexes. We have considered three types of heptacyano environments: two ideal geometries, a pentagonal bipyramid and a capped trigonal prism, and the heptacyanomolybdate fragment of the cyano-bridged magnetic network K2[Mn(H2O)2]3[Mo(CN)7]2.6H2O. At all geometries the first excited Kramers doublet is found remarkably close to the ground one due to a small orbital energy gap in the ligand field spectrum, which ranges between a maximal value in the capped trigonal prism (800 cm(-1)) and zero in the pentagonal bipyramid. The small value of this gap explains (i) the axial form of the g tensor and (ii) the strong magnetic anisotropy even in strongly distorted complexes. Comparison with available experimental data for the g tensor of the mononuclear precursors reveals good agreement with the present calculations for the capped trigonal prismatic complex and a significant discrepancy for the pentagonal bipyramidal one. The calculations for the heptacyanomolybdate fragment of K2[Mn(H2O)2]3[Mo(CN)7]2.6H2O give g(perpendicular)/g(parallel) approximately 0.5 and the orientation of the local anisotropy axis close to the symmetry axis of an idealized pentagonal bipyramid. These findings are expected to be important for the understanding of the magnetism of anisotropic Mo(III)-Mn(II) cyano-bridged networks based on the [Mo(CN)7]4- building block. ispartof: Journal of Physical Chemistry A vol:109 issue:32 pages:7251-7257 ispartof: location:United States status: published

A new approach for the synthesis and organization of cyano-bridged molecule-based magnetic nanoparticles has been developed using a mesostructured hybrid silica containing –(CH2)2C5H4N groups as matrix.

A design of infinite two- and three-dimensional cyano-bridged networks with useful properties has attracted a great deal of attention in contemporary science. A proposal described some investigations in crystal engineering, performed over the past few years on supramolecular coordination polymers based on [Mo(CN) n ] 4− ( n =7,8) building blocks and on their magnetic and intercalation properties.

Reversible release or reabsorption of water like sponges, a process which is accompanied by a dramatic change of structure and magnetic properties, can be achieved by some molecular magnetic materials. When the sponges are hydrated, or wet, the structure consists of isolated units with a nonmagnetic ground state. When the sponges are dehydrated, or dry, the units are linked to each other, affording polymeric molecule-based magnets (see picture).

We report the synthesis of the magnetic molecular compound CoCu(pba)(H2O)3.2H2O, where pba = 1,3-propylenebis(oxamato), which is blue in colour. Its X M T against T behaviour suggests antiferromagnetic correlations between the Co(II)Cu(II)-based ferrimagnetic chains below about 7K. Heating this compound at 130°C in vacuum yields the dehydrated purple compound CoCu(pba).1H2O, which exhibits a transition to the bulk ferromagnetic state at about 33 K, as confirmed by the dc and ac susceptibility measurements. The dehydrated compound is a relatively hard molecular magnet showing a coercive field of 0.3 T at 5 K. The most interesting aspect is its ‘sponge’-like characteristics, that is a complete reversibility of the magnetic properties, as well as the colour change, under a simple dehydration-rehydration process.

The two compounds CoCu(obbz)(H2O)4·2H2O (I) and CoCu(obze)(H2O)4·2H2O (II) have been synthesized, and their crystal structures have been determined at room temperature. Both compounds crystallize in the monoclinic system, space group P21/n. The lattice parameters are a = 7.8190(6) A, b = 12.534(2) A, c = 20.2770(10) A, β = 97.306(6)°, and Z = 4 for CoCu(obbz)(H2O)4·2H2O and a = 17.966(5) A, b = 6.907(1) A, c = 13.678(3) A, β = 97.69(1)°, and Z = 4 for CoCu(obze)(H2O)4·2H2O. For both compounds, the structure consists of isolated Co2+Cu2+ pairs (in which the metal ions are bridged by an oxamide group) and noncoordinated water molecules. A thermogravimetric analysis has been carried out. Three water molecules are removed at a temperature T2 (96 °C for I and 120 °C for II), and five water molecules are removed at a temperature T3 (205 °C for I and 190 °C for II). When cooling down, the two compounds reabsorb water slowly and then return to the initial state. The dehydration−rehydration process is totally reve...

The goal of this paper is to emphasize the multidisciplinary character of molecular magnetism as a whole, and of our own activity in this field. For that, we have briefly described some of our results concerning the theoretical simulation of thermodynamical properties of molecular magnetic materials, the study of spin density maps, and the synergy between optical (or photophysical) and magnetic properties. We have also reported on two new chain compounds exhibiting dominant ferromagnetic interactions, one involving transition metal ions, the other one involving organic radicals.

This paper is devoted to a thorough study of the magnetic properties, both in the dc and ac modes, of two-dimensional ferrimagnetic materials. The general formula of the compounds, abbreviated as A 2 M 2 Cu 3 , is A 2 M 2 [Cu(opba)] 3 nsolv where A + stands for a counter cation (radical cation, alkali-metal or tetraalkylammonium), opba is ortho-phenylenebis(oxamato), M II is Mn II or Co II , and solv is a solvent molecule (Me 2 SO or H 2 O). The dc magnetic susceptibility data for all compounds down to ca. 50 K are characteristic of two-dimensional ferrimagnets. In the A 2 Mn 2 Cu 3 series, three classes of compounds have been distinguished. Class I has a unique representative, A 2 Mn 2 Cu 3 , where A + is the radical cation 2-(1-methylpyridinium-4-yl)-4,4,5,5-tetramethylimadozolin-1-oxyl-3-oxide, the structure of which has already been solved. This compound is a magnet with T c =22.5 K. Class II corresponds to compounds with large cations (tetraethyl- and n-tetrabutylammonium). They also behave as magnets with T c around 15 K. Class III corresponds to compounds with small cations (alkali-metal ions and tetramethylammonium). They behave as metamagnets with a long-range antiferromagnetic ordering in zero field around 15 K, and a field-induced ferromagnetic state. The critical fields are of the order of 0.15 kOe. All the A 2 Co 2 Cu 3 compounds are magnets with T c around 30 K. Furthermore, the cobalt derivatives show a very strong coercivity, with coercive fields of several kOe at 5 K. They also display a pronounced magnetic after-effect in the ordered phase. In the course of this work several peculiar features have been observed. In particular, the A 2 Mn 2 Cu 3 compounds have been found to present weak but significant negative out-of-phase ac magnetic signals at temperatures just above T c . All the observed phenomena are discussed and, in particular, a mechanism for the long-range ordering in these two-dimensional compounds has been proposed.