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Reaction of K3[M(CN)6] (M = CrIII, FeIII, CoIII ) with [Cu(en)2](ClO4)2 in water gives three cyanide-bridged supramolecular complexes, {[Cu(en)2][KM(CN)6]} n [M = CrIII (1), FeIII (2), CoIII (3); en = ethylenediamine], which have been characterized by elemental analysis, ICP analysis, IR spectra, TGA-DTA analysis and X-ray diffraction. Complex 1 crystallizes in the monoclinic, space group C2/c with cell dimensions a = 0.85237(12), b = 1.7014(3), c = 1.2103(2) nm, β = 98.70(2)° and Z = 4, and 2 crystallizes in the same space group with a = 0.8401(2), b = 1.6844(5) A, c = 1.1859(2) nm, β = 98.98(2)° and Z = 4. The crystal structures of 1 and 2 reveal a novel three-dimensional porous framework in which [Cu(en)2]2+ acts as a template, [M(CN)6]3− as a building block and K+ as a connecting unit.

A novel three-dimensional coordination polymer [Mn2(mal)2(H2O)2(μ2-hmt)] n (hmt = hexamethylenetetramine, and mal = malonate) was synthesized and characterized by elemental analysis, crystal structure, IR, TG-DTA and magnetic susceptibility. The compound [Mn2(mal)2(H2O)2(μ2-hmt)] n crystallizes in the orthorhombic system, space group 12 mm, with a = 7.1059(11), b = 7.6986(6), c = 15.9824(13) A, and Z = 2. Mn(II) ion has octahedral geometry coordinated by four oxygen atoms from three malonate, one oxygen atom of water and one nitrogen atom of hmt ligand. The two oxygen atoms of each malonate coordinate to the same Mn(II) ion and the other two oxygen atoms connect to two adjacent Mn(II) ions to form an infinite layer. These layers are bridged by the μ2-hmt ligands to form a three-dimensional structure. The magnetic susceptibility data show that there is an antiferromagnetic exchange interaction in the title compound.

A three-dimensional supramolecular compound [Mn(N3)2(H2O)3(hmt)] 2 , where hmt stands for hexamethylenetetramine, was synthesized and characterized by IR, crystal structure and magnetic susceptibility. The compound [Mn(N3)2(H2O)3(hmt)] n , crystallizes in the orthorhombic system, space group Pn 21 a, with a = 6.5201(9), b = 9.322(2), c = 22.192(3) A, β = 90° and Z = 2. The Mn atom is coordinated in an octahedral arrangement by three nitrogen atoms from three azido ions, and three oxygen atoms from three water molecules, respectively. The azide ligand bridges Mn atoms in μ-1,3 fashion, forming a zigzag chain. Hmt connected with the zigzag chain by hydrogen bonds, to form a three-dimensional supramolecular structure. The magnetic susceptibility data show that there is an antiferromagnetic exchange interaction in the title compound. The data were modeled using an infinite chain model leading to J = -4.8 cm−1.

The copper complex {[Cu(2,2'-bpy)(azpy)(H2O)(ClO4)} n 1 (2,2'-bpy=2,2'bipyridine, azpy=4,4'-azopyridine), has been synthesized and characterized. X-ray analysis reveals that copper is coordinated b...

The complex [Cu(tn)2]2[Co(CN)6](ClO4)·2H2O (tn = trimethylenediamine) has been prepared and characterized by elemental analysis, IR, electronic and electronic spin resonance spectra and magnetic properties. The x-ray structure analysis shows that each [Co(CN)6]3− ion coordinates to four [Cu(tn)2]2+ cations through four cyano nitrogen atoms in the same plane, providing a two-dimensional square network structure, formed from Co-CN-Cu(tn)2-NC-Co linkages.

A heterometallic assembly, [Mn(salen)]2[Ni(CN)4 ]·1/2H2O (where salen=N, N'-ethylene-bis(salicylideneiminato)-dianion), has been prepared from the reaction of [Mn(salen)H2O]ClO4 ·H2O with K2 [Ni(CN)4 ]·H2O in methanol/water. The compound crystallizes in the tetragonal space group P 4/ncc with the cell dimensions of a =14.604(2) A, c =16.949(3) A, and Z=4. The compound assumes a two-dimensional distorted square network structure, formed from Ni―CN―Mn(salen)―NC―Ni linkages with dimensions of Ni―C = 1.867(7)A, Mn―N - 2.312(6) A, Mn―N―C - 163.8(6)° Ni―C―N = 178.4(6)°. The two metal atoms Ni(II) and MN(III) have square and slightly distorted octahedral arrangements, respectively. Magnetic susceptibility measurements indicate the presence of an intramolecular antiferro-magnetic interaction and gives a Mn―Mn exchange integral of −3.2cm−1.

A heterotrinuclear complex, (Cutren)2Fe(CN)6 · 12H2O, was synthesised and its crystal structure solved by direct methods. Crystal data are: C18H60N14Cu2FeO12, M = 847.7, monoclinic, space group: P21/c, a = 13.568(5), b = 10.100(3), c = 13.935(6) A, μ = 95.50(4)°, V = 1901(1) A3, Z − 2. D x = 1.48 gem−3, final R = 0.039 and Rω = 0.049. The crystal structure shows that the complex is composed of two (Cutren) and one hexacyanometallate Fe(CN)6 subunits. Bridging cyano C(l) — N(l) is 1.148(4) A, which is shorter than non-bridging (1.155(4) A and 1.164(4) A). Magnetic properties of (Cutren)2Fe(CN)6 indicate weak ferromagnetic exchange over the temperature range of 6.2–37K.

A new mixed-valence heterotrinuclear complex, Mn(III)Ni(III)Mn(II)O(PhCOO)6Py3, was synthesized using NBu4MnO4 as an oxididant. In the reaction, Ni(II) was oxidized to Ni(III) while Mn(VII) was reduced to Mn(II) and Mn(III). Crystals are monoclinic, space group C2/C, with a = 58.93(4). 6=11.784(3), c = 24.883(9) A, β=100.64(4)°, V= 16983(13) A,3and Dc = 1.35 gem−3 for Z = 12. The crystal structure was solved by direct methods to final R = 0.083, Rω− 0.095. There are two kinds of trinuclear species in the unit cell. One is valence delocalized with Ni(2)—O(2) 1.86(2) A and Mn-O(2) 1.92(1) A (average value of Mn(II)—O and Mn(III)—O). The other is valence localized with Ni(III)—O(1) 1.84(1) A, Mn(III)—O(l) 1.88(1) A and Mn(II)—O(1) 1.97(1) A. Variable temperature (1.5–300K) magnetic susceptibilities indicated an antiferromagnetic exchange interaction among the three metal ions.

The compound CpGdCl2-3THF has been successfully prepared from NaCp (Cp = C5H5) and GdCl3 (2:1 molar ratio) in THF and characterized by elemental analysis, IR and MS spectra and a single crystal X-ray diffraction study, showing that the compound is monomeric in both vapour and solid states. Crystals are monoclinic, space group P21/n, with a = 7.818, b = 17.139(2), c = 15.203(2)A, β = 95.88(2)°, and D c=1.678 g/cm3 for Z=4; 1876 reflections were considered observed. The structure was solved by heavy-atom methods. Least-squares refinement converged to a final value of R=0.041. The gadolinium has a distorted octahedral geometry coordinated by one Cp ring centroid, three THF oxygen atoms and two chloride anions. The average Gd-O(THF) distance is 2.397(3) A. The Gd-C(Cp) bond lengths range from 2.673(6) to 2.691(6)A, and average 2.683(6)A.