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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.

Ferromagnetic resonance was used to study the temperature dependence of mixed manganese-cobalt ferrite nanoparticles with a size range between 5 and 42 nm synthesized by the hydrothermal method. Structural characterization was carried out using X-ray diffraction, scanning, and transmission electron microscopy. M(H) curves as a function of the Mn2+ content at 2.5 and 300 K, and FMR in the temperature range of 80

International audience

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.

This study reports four SMMs based on silanolate or stannanolate ligands cis-[Dy(OSiPh3)2(THF)4][BPh4]·THF·C6H6 (1), cis-[Dy(OSnPh3)2(THF)4][BPh4]·THF·C6H6·C6H14 (2), fac-[Dy(OSiPh3)3(THF)3]·THF (3) and fac-[Dy(OSiPh3)3(bipy)(THF)]·THF (4).

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.

New luminescent cage-like tetranuclear silsesquioxanes [NEt4][(Ph4Si4O8)2(Tb3Eu)(NO3)4(OH)(EtOH)3(H2O)]·4(EtOH) (1) and [NEt4]2[(Ph4Si4O8)2(Tb2Eu2)(NO3)6(EtOH)2(MeCN)2]·4(MeCN) (2) present a tunable thermosensitive Tb3+-to-Eu3+ energy transfer driven by Tb3+ and Eu3+ emission and may be used as temperature sensors operating in the range 41–100 °C with excellent linearity (R2 = 0.9990) and repeatability (>95%). The thermometer performance was evidenced by the maximum relative sensitivity of 0.63% °C−1 achieved at 68 °C.

Yb(iii), Y(iii) and Ca(ii) complexes coordinated by di- and trianionic diiminophenolate ligands.

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 report the synthesis, structures, magnetic and luminescence properties of a series of three-blade propeller homoleptic lanthanide complexes [LnL3](ClO4)3·H2O·2MeCN (Ln = Eu (1), Tb (2), Dy (3), Er (4), Yb (5), Gd (6); L = 2,6-bis(1-methyl-imidazol-2-yl)pyridine). The Eu, Tb, and Dy analogues exhibit the characteristic lanthanide-based luminescence. Remarkably, the mixed Eu/Tb complex with a metal ratio of 1 : 10 can be used as a ratiometric thermometer in the solid-state between 130 and 220 K with the maximum value of Sr = 6.6% K−1 within the range of 150-170 K. Theoretical calculations allow not only modelling of the luminescence properties of pure complexes but also rationalization of the performances of the mixed Eu/Tb thermometers published

Luminescence thermometry allows the remote monitoring of the temperature and holds the promise to drive the next generation of future nano or micrometric devices. Materials able to sense the temperatures are usually based on one or several lanthanide ions allowing a ratiometric measurement. Optimizing the thermometric features is usually achieved through a serendipity approach, but it still appears difficult to accurately predict the sensing performance. Through a combination of experiment and theoretical calculations, we report the first example of an energy-driven luminescent molecular thermometer [Tb0.94Eu0.06(bpy)2(NO3)3] (bpy = 2,2���-bipydine) displaying an exceptional thermal cyclability around room temperature and for which the thermal properties could be theoretically forecasted. This work provides comprehensive guidelines that can be easily extended for any dual-center thermometer in which energy transfer drives the thermometric performance opening the avenue for the smart engineering of sensing devices., This project has received funding from the European Union's Horizon 2020 FET Open programme under grant agreement No 801305 (NanoTBTech).

We investigated a series of Mn

International audience; We investigated a series of Mn(2+)-Prussian blue (PB) nanoparticles Na(z)Mn(x)Fe(1-x)[Fe(CN)(6)](1-y□y)·nH(2)O of similar size, surface state and cubic morphology with various amounts of Mn(2+) synthesized through a one step self-assembly reaction. We demonstrated by a combined experimental-theoretical approach that during the synthesis, Mn(2+) substituted Fe(3+) up to a Mn/Na-Mn-Fe ratio of 32 at% in the PB structure, while for higher amounts, the Mn(2)[Fe(CN)(6)] analogue is obtained. For comparison, the post-synthetic insertion of Mn2+ in PB nanoparticles was also investigated and completed with Monte-Carlo simulations to probe the plausible adsorption sites. The photothermal conversion efficiency (η) of selected samples was determined and showed a clear dependence on the Mn(2+)amount with a maximum efficiency for a Mn/Na-Mn-Fe ratio of 10 at% associated with a dependence on the nanoparticle concentration. Evaluation of the in vitro photothermal properties of these nanoparticles performed on triple negative human breast adenocarcinoma (MDA-MB-231) cells by using continuous and pulsed laser irradiation confirm their excellent PTT efficiency permitting low dose use.

A series of lanthanide dinuclear complexes and chains incorporating two derivatives of cinnamic acid (2-methoxycinnamic acid and 3-methoxycinnamic acid) have been synthesized and characterized by elemental analyses, Infra-Red Spectroscopy, X-ray diffraction, photoluminescence and magnetic measurements. The use of the 2-methoxycinnamic ligand enables the synthesis of two dinuclear complexes (Eu3+ (1), Tb3+ (2)), while the presence of 3-methoxycinnamic acid induces the formation of one-dimensional coordination polymers (Eu3+ (3), Gd3+ (4)). Investigations of the magnetic properties reveals a field-induced slow relaxation of the magnetization for the gadolinium analogue 4, whereas the characteristic Eu3+ luminescence is observed for the europium-based materials 1 and 3.

New luminescent cage-like tetranuclear silsesquioxanes [NEt

International audience

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.

International audience; We demonstrate here that Mn 2+-doped Prussian blue nanoparticles of ca. 55 nm loaded with doxorubicin may be used as efficient therapeutic agents for combined photothermal and chemo-therapy of cancer cells with a synergic effect under two photon irradiation. Photothermal therapy (PTT) is a promising strategy for the therapeutic treatment of tumours, which consists in "burning" cancer cells by laser irradiation at low energy wavelengths in the presence of an NIR photo-adsorbing agent. 1,2 In comparison to conventional cancer treatments, it offers several advantages, such as high specicity, deep penetration, lower tumour recurrence, minimal invasiveness and low toxicity to normal tissues. 3,4 Due to the fact that the treatment efficiency highly depends on the outstanding capacity of the PTT agent to convert light into heat, numerous materials have recently been reported , such as organic dyes 5,6 or various inorganic nano-objects, including metallic nanostructures (Au nanorods or nanoshells, Ag, Pd), carbon based materials (nanotubes, spheres, graphene oxide), transition metal dichalcogenide nanoparticles, metal oxide nano-objects or up-conversion nanocrystals. 7-16 Among these, Prussian blue (PB) nano-objects have been developed as interesting PTT agents since they benet from many advantages, such as: (i) a controlled size ranging from a few to hundreds of nanometers, (ii) easy surface functionali-zation, (iii) excellent absorption properties in the NIR spectral domain due to an Fe 2+ to Fe 3+ intervalence charge transfer band ranging from 650 to 900 nm, (iv) high stability under irradiation , and (v) the fact that bulk PB is validated by the FDA under the brand name Radiogardase® as an antidote for human beings exposed to radioactive Cs +. 17 It has been shown in vitro that PB nanoparticles upon single photon excitation (SPE) (at 808 nm) can convert the laser irradiation into thermal energy contributing to an important temperature increase. 18,19 Their efficiency depends on the nanoparticles' concentration, their chemical composition, the laser power, the mode of irradiation and the irradiation time. Moreover, it has been demonstrated that nano-sized PB presents a higher efficiency in comparison with Au nanorods and a better photothermal stability than organic dyes used as conventional photothermal agents. 19,20 PTT effect of PB nanoparticles has also been demonstrated in vivo through their intra-tumoral injection that causes signicant tumour necrosis 24 h aer NIR irradiation in comparison with non-treated mice. 18 Nevertheless, the complete eradication of cancer cells using solely PTT treatment is rather difficult due to the suboptimal laser energy in deep tissues related to light scattering and absorption effects, a limited light penetration and the insufficient tumour target specicity of PTT agents. Some of these drawbacks may be circumvented using two photon excitation (TPE), which permits to increase the penetration depth and laser focalization allowing selective and efficient destruction of the targeted cancer cells with less damage to healthy tissues. 21-23 In this line of thought, we reported recently Mn 2+-doped PB nanoparticles of ca. 70 nm as efficient multifunctional PTT agents permitting to eradicate 97% of cancer cells 24 h aer irradiation under TPE during 10 min, which may also be followed by Magnetic Resonance Imaging (MRI). 24 However, the comparison between the efficiency of the single and two-photon excitations on the same nano-objects has never been investigated.

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.

We report here a novel “one-pot” approach for the controlled growth and organization of Prussian blue nanostructures on three different surfaces: pure Au0, cysteamine-functionalized Au0, and SiO2-supported lipid bilayers with different natures of lipids. We demonstrate that fine control over the size, morphology, and the degree and homogeneity of the surface coverage by Prussian Blue (PB) nanostructures may be achieved by manipulating different parameters, which are the precursor concentration, the nature of the functional groups or the nature of lipids on the surfaces. This allows the growth of isolated PB nanopyramids and nanocubes or the design of thin dense films over centimeter square surfaces. The formation of unusual Prussian blue nanopyramids is discussed. Finally, we demonstrate, by using experimental techniques and theoretical modeling, that PB nanoparticles deposited on the gold surface exhibit strong photothermal properties, permitting a rapid temperature increase up to 90 °C with a conversion of the laser power of almost 50% for power source heat.

Major-league magnetostriction Magnetoelectric materials polarize in response to either electric or magnetic fields, making them attractive for data-storage applications. Long et al. discovered a ytterbium-based molecular magnetoelectric material with high magnetoelectric coupling (see the Perspective by Zhou and Han). An applied magnetic field strains the material, which changes its electrical properties. The required field is much lower than other magnetoelectric materials, and this work highlights the potential for using molecular materials in devices. Science , this issue p. 671 ; see also p. 627

Tetranuclear [Ni4(CO3)4(pyridine)8·Na]Cl·pyridine·H2O compound with unusual square-planar geometry was obtained via spontaneous fixation of atmospheric CO2 and its conversion into carbonate bridging ligands. This compound exhibits a slow relaxation of the magnetization caused by a spin-glass behaviour.

In view of potential uses in short-term thermochemical heat storage by sorption of water vapor, the capacity to release a sufficient heat amount at the appropriate rate of a Prussian blue analogue (PBA) containing hexacyanocobaltate vacancies has been compared with those of 13X type zeolites possessing Na+, Ce3+, Ce4+, or Tb3+ extra-framework compensating cations. The extended structural and surface characterization demonstrated good reproducibility of the preparation procedures performed on a 10-g scale. The adsorbents were tested under dynamic conditions of gas flow with the aid of either a gas flow calorimeter (120 mL h−1 helium flow) to measure the amount and rate of the integral heat release or a laboratory-scale test rig (15,000 to 22,800 mL h−1 nitrogen flow) to monitor the outlet temperature of nitrogen heated by adsorption. For a regeneration temperature of 353 K and a partial H2O pressure of 2.8 kPa in helium, the PBA sample yielded an integral heat ranging between 900 and 1020 kJ kg−1 with a very slow heat release lasting for even 12–14 h. The zeolite-based materials generated between 350 and 950 kJ kg−1 more rapidly (up to 6–7 h), depending on the nature and the content of compensating cations, as well as on the dehydration state achieved during regeneration. With the laboratory-scale test rig, the efficiency of heat extraction by convection was about 65% for Na-13X and only 38% for PBA, and it diminished with decreasing flow rate.

By means of muon spin relaxation measurements we unraveled the temperature spin dynamics in monodisperse maghemite spherical nanoparticles with different surface to volume ratio, in two samples wit ...

International audience; We report the synthesis, structure and magnetic properties' investigations of a series of new dysprosium heteroleptic mono-and dinuclear complexes based on the association of chloride and different diazabutadiene (DAD 2R = [2,6-iPr2C6H3N-CRCR-NC6H3iPr2-2,6]; R = H, Me) ligands showing different redox states. While using dianionic DAD 2R ligands affords the formation of dichloro-bridged dinuclear complexes [Dy2(DAD 2R)(-Cl)2(THF)2] (R = H (1), Me (2)), two different mononuclear complexes of general formula [DyCl2(DAD 2R)(THF)2] (R = H (3), Me (4)) could be obtained with either a radical monoanionic and a monoanionic DAD 2R state, respectively. Remarkably, all the complexes exhibit a slow relaxation of their magnetization where the relaxation dynamics depends on both, the nuclearity of the system and the DAD 2R redox state.

International audience; We report the synthesis, structure and magnetic investigations of a new Dy 3+ heteroleptic complex [Dy(tBu 4 Carb)(o-Me 2 N-C 6 H 4 CH 2) 2 ]•C 7 H 8 (1) (tBu 4 Carb = 1,3,6,8-Tetra-tert-butyl-9H-carbazole, o-Me 2 N-C 6 H 4 CH 2) 2 = oN ,N-dimethylaminobenzyl). The carbazolyl ligand exhibits an unprecedented  5 -interaction with the magnetically anisotropic dysprosium(III) ion resulting in a genuine zero-field singlemolecule magnet behavior.

International audience; We report the synthesis, structures, magnetic and luminescent properties of a series of heteroleptic lanthanide complexes based on a tripodal tetradentate ligand [Ln(Tpma)(NO 3) 3 ]•nMeCN (Ln = Eu (1), Tb (2), Dy (3), Er (4), n = 0.5; Yb (5), n = 0; Tpma = tris((1H-pyrazol-1-yl)methyl)amine). The europium, terbium and dysprosium analogues exhibit a lanthanide-based luminescence, while dysprosium, erbium and ytterbium compounds show a field-induced slow relaxation of their magnetization involving Raman and direct processes.

International audience; We report on the synthesis, structure, magnetic and luminescence properties investigations of four new cagelike lanthanide-based silsesquioxanes (Cat)2[(PhSiO1.5)8(LnO1.5)4(O)(NO2.5)6(EtOH)2(MeCN)2] (where Cat + = Et4N + , PPh4P + and Ln 3+ = Eu 3+ Tb 3+ and (Ph4P)4[(PhSiO1.5)8(TbO1.5)4(O)2(NO2.5)8]•10MeCN. They present an unusual prism-like topology of cage architectures and lanthanide-characteristic emission, which makes them the first luminescent cage-like lanthanide silsesquioxanes. One of the Tb 3+-based cages presents a magnetic spin-flip transition.

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+.

We report the synthesis, photoluminescence and magnetic properties of two octahedral dysprosium complexes [DyR2(py)4][BPh4]·2py (1) and [DyR2(THF)4][BPh4] (2) (R = carbazolyl, py = pyridine, THF = tetrahydrofuran) exhibiting a quasi linear N-Dy-N angle in the axial direction, suitable for providing a coordination environment allowing the zero-field slow relaxation of magnetization.