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International audience; A monodimensional heterotrimetallic coordination polymer of formula ∞ 1 [{Cu II Mn II L 2 } 3 {(µ-NC) 3 W V (CN) 5 } 2 ]·H 2 O (1) has been assembled from pre-designed [Cu II Mn II L 2 ] 2+ cationic modules and homoleptic [W V (CN) 8 ] 3-metalloligands (H 2 L 2 is the compartmental Schiff-base resulting from the stepwise condensation of 2,6-diformyl-p-cresol with ethylenediamine and di-Polynuclear complexes containing different paramagnetic metal ions are of high interest in molecule-based magnetism. [1] The large majority of the heterometallic molecular systems are constructed from two different metal ions. Conversely, complexes with three different paramagnetic centers are significantly less common, mainly because of the difficulties related to the scrambling of the metal ions. [2] A rational synthetic approach towards heterotrimetallic complexes consists of assembling preformed heterobimetallic modules and metalloli-gands. [2] Anionic cyanido complexes, homo-and heteroleptic, are excellent metalloligands for building magnetic molecule-based materials containing two, or more, different metal ions. [3] Our work in this field of research has been focused on the use of heterobimetallic tectons like phenoxido-bridged 3d-3d′ and 3d-4f complexes, with the metal ions enclosed into different coordination sites generated by dissymmetric macrocyclic or [a] Dr. 3111 ethylenetriamine). The magnetic properties of 1 have been investigated revealing a three-dimensional ordered antiferromag-netic ground state below 4 K resulting from different antiferro-magnetic interactions between all the spin carriers (S = 1/2 Cu II , S = 5/2 Mn II , and S = 1/2 W V centers). side-off compartmental ligands. [4] Indeed, most of the known heterotrimetallic complexes are assembled using 3d-4f precursors , which are easily obtained by exploiting the differences between 3d and 4f metal ions [coordination numbers, HSAB-"hard and soft (Lewis) acids and bases"-behavior] and using side-off compartmental ligands. [5] The synthesis of 3d-3d′ magnetic building-blocks is more delicate, since the differences mentioned above are less prominent. One appropriate pair is composed of Cu II and Mn II ions, especially because Mn II does not have a particular stereochemical preference, while Cu II does. Robust binuclear Cu II-Mn II complexes have been generated using side-off compartmental ligands (like H 2 L 1 see Scheme 1) with an open compartment that allows various coordination numbers and geometries for the Mn II ion, while the inner compartment hosts a Cu II metal ion with a square-planar or square-pyramidal geometry (Scheme 1). [6] Scheme 1. For analogous bis-phenoxido-bridged Cu II-Mn II binuclear complex, [Cu II Mn II L 2 ] 2+ (Scheme 1), the metal ions are held together by a dissymmetric compartmental Robson-type ligand. [7] Both binuclear systems are characterized by an S = 2 ground state, which results from a significant antiferromagnetic interaction between S = 1/2 Cu II and S = 5/2 Mn II centers, and are thus good building-block candidates for designing heterotrimetallic magnetic complexes and networks. For example, the self-as

International audience; The polynuclear compounds containing anisotropic metal ions often exhibit efficient barriers for blocking of magnetization at fairly arbitrary geometries. However, at variance with mononuclear complexes, which usually become single-molecule magnets (SMM) under the sole requirement of a highly axial crystal field at the metal ion, the factors influencing the SMM behavior in polynuclear complexes, especially, with weakly axial magnetic ions, still remain largely unrevealed. As an attempt to clarify these conditions, we present here the synthesis, crystal structures, magnetic behavior, and ab initio calculations for a new series of NiII–LnIII–WV trimetallics, [(CN)7W(CN)Ni(H2O)(valpn)Ln(H2O)4]·H2O (Ln = Y 1, Eu 2, Gd 3, Tb 4, Dy 5, Lu 6). The surprising finding is the absence of the magnetic blockage even for compounds involving strongly anisotropic DyIII and TbIII metal ions. This is well explained by ab initio calculations showing relatively large transversal components of the g-tensor in the ground exchange Kramers doublets of 1 and 4 and large intrinsic tunneling gaps in the ground exchange doublets of 3 and 5. In order to get more insight into this behavior, another series of earlier reported compounds with the same trinuclear [WVNiIILnIII] core structure, [(CN)7W(CN)Ni(dmf)(valdmpn)Ln(dmf)4]·H2O (Ln = GdIII 7, TbIII 8a, DyIII 9, HoIII 10), [(CN)7W(CN)Ni(H2O)(valdmpn)Tb(dmf)2.5(H2O)1.5]·H2O·0.5dmf 8b, and [(CN)7W(CN)Ni(H2O)(valdmpn)Er(dmf)3(H2O)1]·H2O·0.5dmf 11, has been also investigated theoretically. In this series, only 8b exhibits SMM behavior which is confirmed by the present ab initio calculations. An important feature for the entire series is the strong ferromagnetic coupling between Ni(II) and W(V), which is due to an almost perfect trigonal dodecahedron geometry of the octacyano wolframate fragment. The reason why only 8b is an SMM is explained by positive zero-field splitting on the nickel site, precluding magnetization blocking in complexes with fewer axial Ln ions. Further analysis has shown that, in the absence of ZFS on Ni ion, all compounds in the two series (except those containing Y and Gd) would be SMMs. The same situation arises for perfectly axial ZFS on Ni(II) with the main anisotropy axis parallel to the main magnetic axis of Ln(III) ions. In all other cases the ZFS on Ni(II) will worsen the SMM properties. The general conclusion is that the design of efficient SMMs on the basis of such complexes should involve isotropic or weekly anisotropic metal ions, such as Mn(II), Fe(III), etc., along with strongly axial lanthanides.

International audience; Three families of heterotrimetallic chains (type 1-type 3), with different topologies, have been obtained by reacting the 3d-4f complexes, [Cu(L1)xLn(NO3)3] with x = 1 or 2, formed in situ by the reaction of Schiff-base bi-compartmental [CuII(L1)] complexes and lanthanide(iii) salts, with (NHBu3)3[M(CN)8] (M = MoV, WV). For type 1 series of compounds, 1-D coordination polymers, with the general formula [Cu2(valpn)2LnM(CN)8][middle dot]nH2O[middle dot]mCH3CN (where H2valpn = 1,3-propanediylbis(2-iminomethylene-6-methoxy-phenol), result from the association of trinuclear CuII2LnIII moieties and [MV(CN)8]3- anions acting as tri-connecting spacers [Ln = La (1), Ce (2), Eu (3), Tb (4), Ho (5), M = Mo; Ln = Tb (6), Ho (7), M = W; m = 0, n = 1.5 (7) and 2 (1-4, 6); n = 1, m = 1 (5)]. The type 2 family has the general formula [Cu(valdp)Ln(H2O)4M(CN)8][middle dot]2H2O[middle dot]CH3CN (where H2valdp = 1,2-propanediylbis(2-iminomethylene-6-methoxy-phenol)) and also consists of heterotrimetallic chains involving binuclear CuIILnIII units linked to [M(CN)8]3- anions coordinating through two cyano groups [Ln = Gd (8), Tb (9), Dy (10); M = Mo; Ln = La (11), Gd (12), Tb (13), Dy (14); M = W]. With large LnIII ions (LaIII and PrIII), the type 3 family of heterotrimetallic compounds are assembled: [Cu2(valdp)2Ln(H2O)4Mo(CN)8][middle dot]nCH3OH[middle dot]mCH3CN, n, m = 0, Ln = La (15); n = m = 1, Pr (16), in which the trinuclear CuII2LnIII nodes are connected to [MoV(CN)8]3- anions that act as tetra-connecting spacers. For TbIII derivatives of the type 1 (compounds 4 and 6), the DC magnetic properties indicate a predominant ferromagnetic CuII-TbIII interaction, while the AC magnetic susceptibility (in the presence of a static magnetic field, HDC = 3000 Oe) emphasize the slow relaxation of the magnetization (Ueff/kB = 20.55 K and [small tau]0 = 5.5 [times] 10-7 s for compound 4, Ueff/kBT = 15.1 K and [small tau]0 = 1.5 [times] 10-7 s for compound 6). A predominant ferromagnetic CuII-LnIII interaction was also observed in the type 2 series (compounds 8-10 and 12-14) as a result of the magnetic coupling between copper(ii) and lanthanide(iii) ions via the phenoxo-bridge. The magnetic behavior for the LaIII derivatives reveals that weak ferromagnetic interactions are also operative between the CuII and the 4d/5d centers.

Infrared and Raman spectra of the three chiral molecular conductors (EDT-TTF-OX)_2AsF_6, comprising two salts based on enantiopure EDT-TTF-OX donor molecules and one based on their racemic mixture, have been measured as a function of temperature. In the frequency range of the C=C stretching vibrations of EDT-TTF-OX, charge-sensitive modes are identified based on theoretical calculations for neutral and oxidized EDT-TTF-OX using density functional theory (DFT) methods. The positions of the C=C stretching modes in both Raman and infrared spectra of the (EDT-TTF-OX)_2AsF_6 materials are analyzed assuming linear relationship between the frequency and charge on the molecule. The charge density on the EDT-TTF-OX donor molecule is estimated to be +0.5 in all the investigated materials and does not change with temperature. Therefore it is suggested, that M-I transition observed in (EDT-TTF-X)_2AsF_6 chiral molecular conductors at low temperature is not related to the charge ordering mechanism., Comment: 9 pages, 6 figures, uses cej.cls, conference contribution to be submitted to Central European Journal of Physics, conference info: WOREN'2013, Workshop on Organic Electronics and Nanophotonics, February 17-21, 2013, Z\lockie, Poland

International audience; Sixteen new 3d–4f binuclear complexes have been obtained using two Schiff-base ligands, Hvalampy and Hvalaepy, derived from the reaction of o-vanillin and 2-aminomethyl-pyridine or 2-(2-aminoethyl)-pyridine, respectively. Hvalaepy ligand: [Zn(valaepy)2Sm(O2NO)3]·CH3CN 1; [Ni(valaepy)2Eu(O2NO)3(H2O)]·CH3CN 2; [Ni(valaepy)2Gd(O2NO)3(H2O)]·CH3CN 3; [Ni(valaepy)2Dy(O2NO)3(H2O)]·CH3CN 4; [Ni(valaepy)2Ho(O2NO)3(H2O)]·CH3CN 5; [Cu(valaepy)2Eu(O2NO)3]·CH3CN 6; [Cu(valaepy)2Gd(O2NO)3]·CH3CN 7; Hvalampy ligand: [Zn(valampy)2Pr(O2NO)3]·CH3CN 8, [Zn(valampy)2Sm(O2NO)3]·CH3CN 9; [Zn(valampy)2Gd(O2NO)3]·CH3CN 10; [Zn(valampy)2Tb(O2NO)3]·CH3CN 11; [Zn(valampy)2Dy(O2NO)3]·CH3CN 12; [Zn(valampy)2Eu(O2NO)3]·CH3CN 13; [Ni(valampy)2La(O2NO)3(H2O)2]·2H2O 14, [Ni(valampy)2Sm(O2NO)3(H2O)2]·2H2O 15; [Ni(valampy)2Eu(O2NO)3(H2O)]·2CH3CN 16. The crystal structures of the sixteen compounds can be described as resulting from the coordination of two valaepy− (or valampy−) ligands to the 3d metal ions through two phenoxo oxygen atoms and nitrogen atoms, arising from the pyridyl and azomethynic groups. In all these compounds the 3d and 4f metal ions are bridged by the phenoxo oxygen atoms. The comparative analysis of the crystal structures shows several differences, which arise mainly from the stereochemical preference of the 3d metal ions. These ions arrange the two organic ligands in positions that favour or not the coordination of the methoxy groups to the lanthanide ions. The magnetic properties of compounds 2, 3, 4, 5, 7, 14, 15, and 16 have been investigated. The exchange interactions between NiII and GdIII in 3, and between CuII and GdIII in 7 were found to be ferromagnetic (JNiGd = 1.56 cm−1; JCuGd = 4.94 cm−1; H = −JSGdSM). For the 3d–4f binuclear complexes derived from the Hvalampy ligand (namely 8–13) the photoluminescence (PL) properties were investigated in the Vis spectral region. The results provide evidence for the relatively stronger antenna effect in 9 and 11 compared to 8, 12 and 13.

International audience

An unsymmetrical bis(tridentate) ligand LH in which one binding site can be readily deprotonated forms a kinetically inert [Co(III)L(2)](+) complex which can be used as a "corner" species for the "Coupe du Roi" assembly of trans,trans-[Co(2)M(2)L(4)](6+) metallogrids (M = Fe(II), Co(II), Cu(II), Zn(II)). In the mixed Co(III)/Co(II) species, the oxidation states appear to be localised. In solution, the ligand LH forms octacationic, homometallic [2 × 2] grids with the individual labile metal ions Fe(II), Co(II), Cu(II), Zn(II), seemingly as mixtures of all possible isomers arising from the unsymmetrical nature of the ligand. In the solid state, however, [Zn(4)L(4)](CF(3)SO(3))(8)·4CH(3)CN crystallises as a single species where the cation has S(4) symmetry. This stereoselectivity in the crystalline lattice is associated with interactions between the cation and triflate anions which can again be analysed in terms of the Coupe du Roi concept.

International audience; Heterobinuclear [CuIIMnII] and [CuIICoII] cationic complexes can efficiently act as nodes for designing coordination polymers. The crystal structures of two binuclear precursors, [LCuCo(NO3)2] (1) and [LCuMn(NO3)2] (2), have been solved (L2− is the dianion of the Schiff base resulting from the 2 : 1 condensation of 3-methoxysalicyladehyde with 1,3-propanediamine). The nitrato ligands, coordinated to CoII and, respectively, the MnII ions from the precursors, are easily replaced by exo-dentate ligands, resulting in 1-D coordination polymers: 1∞[L(H2O)CuCo(oxy-bbz)]·CH3CN·C2H5OH (3), 1∞[L(H2O)CuCo(2,5-dhtp)]·CH3CN (5) and ∞[L(H2O)CuMn(ox)]·3H2O (6) (oxy-bbz2− = the dianion of 4,4′-oxy-bis(benzoic) acid; 2,5-dhtp2− = the dianion of 2,5-dihydroxy-terephthalic acid; ox2− = the dianion of the oxalic acid). In the case of the [CuMn] node, the interaction with oxy-bbz2− affords a binuclear complex, [LCuMn(oxy-bbz)(H2O)2] (4).

International audience; By connecting [LCuTb](3+) nodes with [Fe(CN)(6)](3-) spacers a 1-D coordination polymer with slow relaxation of magnetization is obtained (L(2-) is the N, N'-propylene-bis(3-methoxy-salicylideneiminato) anion).

International audience; The self-assembly process involving the dianion of trimesic acid (Htrim2−) and {Cu(tmen)}2+ templating cations (tmen = N,N,N′,N′-tetramethylethylenediamine) affords a new metallacalixarene, [Cu4(tmen)4(Htrim)4]·nH2O. The packing of the cyclic molecules in the crystal generates channels that are filled by water molecules. The dehydration−rehydration process of the crystals was found to be reversible.

International audience; The synthesis and crystal structure of the first tetrathiafulvalene (TTF) based radical cation salt containing the heteroleptic paramagnetic anion [CrIII(2,2′-bipy)(C2O4)2]− are reported. In the salt formulated as α′-(BEDT-TTF)2[Cr(C2O4)2(2,2′-bipy)]·CHCl2CH2Cl according to the single-crystal X-ray structure, the BEDT-TTF (bis(ethylenedithio)tetrathiafulvalene) donors are in a mixed valence state and form two types of uniform chains within organic layers. Two overlap modes are observed in these chains, which are canted with respect to the stacking direction, leading to a peculiar α′ packing mode. The anions organize in supramolecular chains sustained by π–π interactions between the bipyridine units. The magnetic behavior of the compound follows a Curie–Weiss law, with a magnetic contribution arising from both cationic and anionic counterparts. Single-crystal electrical transport measurements are in agreement with a semiconductor behavior and have been correlated with extended Hückel tight-binding calculations.

Five new bimetallic compounds have been synthesized and crystallographically characterized: [{Cu(acac)(phen)}2{Ni(CN)4}] * H2O (1), [{Cu(acac)(bipy)}2{Ni(CN)4}] (2); [Cu(acac)(bipy)(H2O)]2[Ni(CN)4] (3), [(Cu(acac)(Me2bipy)]2[Ni(mnt)2] (4), [Cu(acac)(bipy)][Ni(mnt)2] (5) (Me2bipy=4,4′‐dimethyl‐2,2′‐bipyridine; mnt=maleonitriledithiolate). The molecular structures of complexes 1 and 2 are similar: they consist of neutral [{Cu(acac)(BB)}2{Ni(CN)4}] entities, which result by connecting two [Cu(acac)(BB)]+ ions through two trans‐cyano groups from the bridging ligand, [Ni(CN)4]2− (BB=1,10‐phenanthroline and, respectively, 2,2′‐bipyridine). The intermolecular π‐π stacking interactions established between the organic ligands attached to the copper ions lead to supramolecular chains. In the ionic compound 3, the [Ni(CN)4]2− anions and the [Cu(acac)(bipy)(H2O)]+ cations generate a 3D supramolecular architecture by convolution of hydrogen bonding with π‐π stacking interactions. The crystal structure of compound 4, [(Cu(acac)(Me2bipy)]2[Ni(mnt)2], consists of cationic, [(Cu(acac)(Me2bipy)]+, and anionic species, [Ni(mnt)2]2−, which are connected through Cu *** S interactions, resulting in supramolecular {CuNiCu} trimers. Crystal 5 is an ionic compound containing [Cu(acac)(bipy)]+ and [Ni(mnt)2]− ions.

International audience; Racemic and enantiopure ethylenedithio-tetrathiafulvalene-thiomethyl-oxazoline (EDT-TTF-(SMe)-OX) derivatives have been synthesized. Single-crystal X-ray diffraction analyses reveal the establishment of OS nonbonded interactions, unprecedented in the TTF series, characterized by short SO distances and linear OSMe motifs. Theoretical calculations at the DFT/B3LYP level on a model molecule demonstrate that both possible planar s-trans (OS interaction) and s-cis (NS interaction) conformations are energy minima, separated by an extremely weak energy gap. The energy barrier corresponding to the equilibrium between the two forms has been also estimated from DFT calculations, as well as their relative stability in the radical cation state of the TTF. According to the latter, there is a slight tendency towards the enhancement of the NS interactions. Following the predictions of the theoretical calculations, the coexistence of both OS and NS nonbonded interactions is observed in two mixed valence radical cation salts of the racemic TTF with the dianionic cluster Mo6Cl14, prepared upon electrocrystallization. Interestingly, the ratio TTF : dianion is finely tuned by the choice of the electrocrystallization solvent. Physical measurements such as electrical conductivity and thermoelectric power on single crystals combined with magnetic susceptibility data in one case and extended Hückel tight-binding calculations demonstrate and rationalize the semiconducting behavior of both mixed valence salts. This study demonstrates that intramolecular NS and OS interactions can efficiently modulate and direct in the TTF series the occurrence of original solid-state structures provided with physical properties.

WOS; International audience; Three new heterobimetallic 1D coordination polymers have been obtained by assembling the [Ni(bpca)2] complex, as a building block, with lanthanide cations: [{Ln(O2NO)(H2O)3}- {Ni(bpca)2}](NO3)2·3H2O (Ln Gd 1; Tb 2; Dy 3). The three compounds are isostructural and their structure consists of infinite cationic chains with LnIII ions connected by [Ni- (bpca)2] complexes acting as bridging bis-bidentate ligands. The charge of the chains is counterbalanced by uncoordinated nitrate ions. The LnIII ions display a coordination number of nine: four oxygen atoms from the carbonyl groups of the bpca ligands belonging to two {Ni(bpca)2} moieties, two oxygen atoms from a chelating nitrato ion and threewater molecules. The magnetic investigation of the gadolinium derivative 1 revealed very weak intrachain NiII–GdIIIferromagnetic interactions (θ = +0.15 K). The weak intrachain- exchange interactions, as well as the bad magnetic isolation of the chains in the crystals, preclude the single-chain magnet behaviour of compounds 2 and 3. The out-of-phase, χ, signal observed with compounds 2 and 3 can be ascribed to the magnetic slow relaxation of the lanthanide ions (TbIII, DyIII).

Novel supercomplexes are constructed from a mononuclear square planar Ni(II) or Pd(II) complex acting as a host receptor towards the aqua ligand from copper complexes.

Three 1-D copper(II) coordination polymers have been obtained by using the nicotinato anion (NA(-)) as a bridge, and 2,2'-bipyridine or dicyanamide (dca) as coligands: [Cu-1(infinity)2(bipy)(2)(NA)(2)](ClO4)(2)center dot H2O 1, [Cu-1(infinity)2(Me(2)bipy)(2)(NA)(2)](ClO4)(2) 2, [Cu-1(infinity)3(NA)(4)(dca)(2)(H2O)(8)]center dot 2H(2)O 3 (bipy = 2,2'-bipyridine; Me(2)bipy = 4,4'-dimethyl-2,2'-bipyridine, dca = dicyanamide anion). The metal-ligand association in compounds 1 and 2 is very similar and generates tubelike coordination polymers, which are constructed from pairs of copper atoms connected through two carboxylato groups from two NA(-) ligands. Each pyridyl moiety from the NA(-) ligand coordinates at the apical position of the copper ions from another pair, resulting in chains running along the crystallographic c axis. The structure of 3 consists of infinite ladderlike chains: the rungs are formed by trinuclear [Cu-3] moieties, with the copper(II) ions connected through NA- bridges, the ladder sides being constructed from dca(-) bridging ligands. The cryomagnetic investigation of the three compounds reveals weak antiferromagnetic interactions mediated by the nicotinato ligand, 1: J = -7.3 cm(-1), 2: -15.3 cm(-1), 3: -0.58 cm(-1).