([CuII(tn)]2[FeII(CN)6])· KCl·5H2O (tn=1,3-diaminopropane): A two-dimensional bimetallic layered material with "Cu4Fe3" defective cubane units

International audienceThe new two-dimensional coordination compound ([CuII(tn)]2[-FeII(CN)6]) ·KCl·5H2O (1) (tn=1,3-diaminopropane), generated by six -Fe-CN-Cu- bridges, shows weak ferromagnetic interactions between the nearest Cu(II) ions through the diamagnetic [Fe(CN)6]4- anion

[Cu(tn)]3[Cr(CN)6]2·3H2O: A unique two-dimensional Cu-Cr cyano-bridged ferromagnet (tn = 1,3-diaminopropane)

International audienceReaction of the two-coordinate 'assembling complex-ligand' [Cu(tn)]2+ with the building block [Cr(CN)6]3- leads to a unique two-dimensional Cu-Cr cyano-bridged ferromagnet with unusual μ3- and μ4-bridging [Cu(tn)]2+ units

New magnetic copper(II) coordination polymers with the polynitrile ligand (C[C(CN)2]3)2- and N-donor Co-ligands

cited By 45International audienceReactions between CuCl2 and K2tcpd (tcpd2- = [C10N6]2 = (C[C(CN)2] 3)2-) in the presence of neutral co-ligands (bpym = 2,2′-bipyrimidine, and tn = 1,3-diaminopropane) in aqueous solution yield the new compounds [Cu2-(bpym)(tcpd)2(H2O) 4]·2H2O (1), [Cu(tn)(tcpd)] (2), and [Cu(tn) 2(tcpd)]·H2O (3), which are characterized by X-ray crystallography and magnetic measurements. Compound 1 displays a one-dimensional structure in which the bpym ligand, acting with a bis-chelating coordination mode, leads to [Cu2(bpym)]4+ dinuclear units which are connected by two μ2-tcpd2- bridging ligands. Compound 2 consists of a three-dimensional structure generated by [Cu(tn)]2+ units connected by a μ4-tcpd2- ligand. The structure of 3 is made up of centrosymmetric planar [Cu(tn)2+ units connected by a μ2-tcpd2- ligand leading to infinite zigzag chains. In compounds 1 and 3, the bridging coordination mode of the tcpd2- unit involves only two nitrogen atoms of one C(CN)2 wing, while in 2, this ligand acts via four nitrogen atoms of two C(CN)2 wings. Despite this difference, the structural features of the tcpd2- units in 1-3 are essentially similar. Magnetic measurements for compound 1 exhibit a maximum in the χm vs T plot (at ∼150 K) which is characteristic of strong antiferromagnetic exchange interactions between the Cu(II) metal ions dominated by the magnetic exchange through the bis-chelating bpym. The fit of the magnetic data to a dimer model gives J and g values of -90.0 cm-1 and 2.12, respectively. For compounds 2 and 3 the thermal variations of the magnetic susceptibility show weak antiferromagnetic interactions between the Cu(II) metal ions that can be well reproduced with an antiferromagnetic regular S = 1/2 chain model that gives J values of -0.07(2) and -0.18(1) cm-1 with g values of 2.12(1) and 2.13(1) for compounds 2 and 3, respectively (the Hamiltonian is written in all the cases as H = -2JSaSb). © 2005 American Chemical Society

A two-dimensional magnetic architecture with bridging polynitrile and 2,2′\prime -bipyrimidine ligands

A new polymeric, two-dimensional compound [ Co$_{2}$(bpym)(dcne)$_{4}$(H$_{2}$O)$_{2}$] (1) (dcne$^{- }$= [ (CN)$_{2}$CC(O)OEt)] $^{-}$ = 2,2-dicyano-1-ethoxyethenolate anion and bpym = 2,2' bipyrimidine) has been synthesized and characterized by X-ray crystallography. The structure is monoclinic space group $P$2$_{1}$/$a$ and consists of two-dimensional networks of octahedrally co-ordinated Co(II) ions, bridged by bis-bidentate 2,2'-bipyrimidine and $\mu _{2}$-dcne anions. Magnetic measurements revealed a broad maximum in the $\chi$$_{m }$vs T plot at 20 K which is characteristic of antiferromagnetic exchange between the high spin cobalt(II) centres. Key words. Cobalt complexes, magnetic measurements, 2.2'-bipyrimidine

New charge transfer salts of two organic π-donors of the tetrathiafulvalene type with the paramagnetic [Cr(NCS)6]3- anion

cited By 9International audienceThe electrochemical combination of the paramagnetic anion [Cr(NCS)6]3- with the organic π-donors bis(ethylenedithio)tetrathiafulvalene (ET) and 4,5-bis(2-hydroxyethylthio) -4′,5′-ethylenedithiotetrathiafulvalene (DHET-EDTTTF) leads to two new radical cation salts, namely (ET)4 [Cr(NCS 6]·PhCN 1 and (DHET-EDTTTF)2 (NEt4)[Cr(NCS)6] 2. Both have been characterized by X-ray crystallography, magnetic and resistivity measurements. The structure of 1 consists of alternating inorganic layers generated by the anions and organic layers in which the PhCN molecules are inserted; the organic sub-lattice is built up from four different ET units, three of them with a charge distribution of +1, the fourth being neutral. The organic sub-lattice of 2 contains a centrosymmetric [(DHET-EDTTTF•)2]2+ dimer, in which the overlap mode is of the eclipsed type. Conductivity measurements indicate that compounds 1 and 2 are semiconductors with room temperature conductivities of 1.4 × 10-2 and 6.1 × 10-5 S cm-1 and activation energies of 0.24 and 0.23 eV, in 1 and 2, respectively. For both salts, magnetic measurements indicate (i) that the organic and inorganic parts are magnetically independent, and (ii) that the organic units are antiferromagnetically coupled. To cite this article: F. Thétiot et al., C. R. Chimie 6 (2003). © 2003 Académie des sciences. Published by Éditions scientifiques et médicales Elservier SAS. All rights reserved