Chemistry Journal of Moldova

Inorganic and coordination chemistry

MAGNETIC INVESTIGATION OF AN UNUSUAL DISSYMMETRIC BINUCLEAR MANGANESE CARBOXYLATE COMPLEX

Author(s):

Ghenadie Novitchi, Jean-Pierre Costes, Lilia Popovschi, Sergiu Shova, Aurelian Gulea


Field: Inorganic and coordination chemistry
Type: Research paper
Issue: 2006 Volume 1, no.1
Pages: 97-99
Keywords: manganese(II) carboxylates; magnetic properties.
Full Text (PDF): Download
Abstract (JPEG)

DOI:
dx.doi.org/10.19261/cjm.2006.01(1).03

Graphical Abstract:
 The magnetic susceptibility (χT) of an unusual dissymmetric binuclear manganese corboxylate complex has been measured from 2 to 300K. The magnetic data which have been fitted with help of the Heisenberg Dirac Van Vleck HDVV spin-exchange Hamiltonian H = − J S 1 S 2 , indicate that an antiferromagnetic interaction equal to J = -0.90(1) cm-1 is present. A correlation between J values and Mn-H2O-Mn angles has been tempted.

Downloads: 19

[Cr3O(CH3COO)6(H2O)3]NO3⋅HNO3⋅H2O, TRIAQUA-HEXAKIS(μ- ACETATO)-μ3-OXO-TRICHROMIUM(III) NITRATE NITRIC ACID SOLVATE MONOHYDRATE

Author(s):

Marco Bettinelli, Adolfo Speghini, Gabriele Bocelli, Olesea Gherco, Valeriu Mereacre, Denis Prodius, Constantin Turta


Field: Inorganic and coordination chemistry
Type: Research paper
Issue: 2006 Volume 1, no.1
Pages: 88-96
Keywords: Chromium carboxylate, Polynuclear complex, UV-Vis.
Full Text (PDF): Download
Abstract (JPEG)

DOI:
dx.doi.org/10.19261/cjm.2006.01(1).04

Graphical Abstract:
 Reaction in methanol solution of the trinuclear ‘basic’ chromium(III) acetate with Pr(NO3)3⋅5H2O and further extraction by chloroform-acetone mixture led to the formation of novel unusual [Cr3O(CH3COO)6(H2O)3]NO3⋅HNO3⋅H2O (1) cluster with one “free” molecule of nitric acid. Complex 1 crystallizes in the monoclinic space group P21/c with, at room temperature, a = 13.624(2), b = 15.032(2), c = 15.180(2) Å, β = 112.98(3) °, Z = 4, and V = 2862.09 Å3. The obtained crystalline compound has been synthesized and characterized by IR and UV/Vis methods.

Downloads: 20

SYNTHESIS AND PHYSICO-CHEMICAL STUDIES OF HETEROMETALLIC NITRILOTRIACETATES OF CHROMIUM(III) WITH SOME 3d METALS

Author(s):

Victor Ciornea, Aurelian Gulea


Field: Inorganic and coordination chemistry
Type: Research paper
Issue: 2006 Volume 1, no.1
Pages: 84-87
Keywords: heterometallic, nitrilotriacetates, chromium(III), 3d metals, bipyridine.
Full Text (PDF): Download
Abstract (JPEG)

DOI:
dx.doi.org/10.19261/cjm.2006.01(1).05

Graphical Abstract: 
Heterometallic complexes of chromium (III) with some 3d metals have been synthesized based on nitrilotriacetic acid (H3nta), like M(bpy)2Cr2(OH)2(nta)2·nH2O, where M = Mn2+, Co2+, Ni2+ and Zn2+; bpy = α,α′- bipyridine; n = 8 or 9. Their chemical composition has been determined from the results of the elemental analysis and thermogravimetric study. The coordination modes of the nta3 ̄ ligand and the type of chemical bonds have been proposed basing on IR spectra.

Downloads: 20

THE SYNTHESIS AND STUDY OF TETRANUCLEAR CLUSTER [Fe4O2(CCl3COO)8(THF)2(DMF)(H2O)]⋅THF

Author(s):

Denis Prodius, Valeriu Mereacre, Sergiu Shova, Maria Gdaniec, Yurii Simonov, Lorenzo Sorace, Andrea Caneschi, Nicolae Stanica, Ion Geru, Constantin Turta


Field: Inorganic and coordination chemistry
Type: Research paper
Issue: 2006 Volume 1, no.1
Pages: 77-83
Keywords: {Fe4O2} core; Homotetranuclear carboxylate; Crystal structure; Antiferromagnetic exchange.
Full Text (PDF): Download
Abstract (JPEG)

DOI:
dx.doi.org/10.19261/cjm.2006.01(1).09

Graphical Abstract:
 The novel bis(μ3-oxo) tetranuclear trichloracetate cluster, [Fe4O2(CCl3COO)8(THF)2(DMF)(H2O)]⋅THF (1), has been synthesised and subsequently characterised by X-ray structure analysis, magnetic measurements and infra red (IR). The structure of cluster is “butterfly” type. The Fe···Fe separation has the value of 2.883(1) - 3.441(7) Å. The coordination number of iron (III) is 6. Magnetic studies reveal the presence of an antiferromagnetic exchange in the parallelogram skeletons of the tetranuclear species. Using the spin Hamiltonian H = -2Jwb(Ŝ1Ŝ2 + Ŝ2Ŝ3 + Ŝ3Ŝ4 + Ŝ4Ŝ1) - 2JbbŜ2Ŝ4v+ gμβ(Ŝ1z + Ŝ2z +Ŝ3z + Ŝ4z)B, the fitting parameters Jbb = - 14.3 cm-1, Jwb = - 32.1 cm-1 , g = 2.07, ρparam. -5 impur. = 4.2 %, ΘCurie-Weiss const. = -0.5 K and R = 6.8·10 were obtained.

Downloads: 18

HOMO- AND HETERONUCLEAR COMPLEXES OF COPPER (II) WITH SCHIFF BASE OBTAINED ON THE BASE OF 2-HYDROXY-3-CARBOXYNAPHTALDEHYDE

Author(s):

A.G. Lazarescu, T.C. Popa


Field: Inorganic and coordination chemistry
Type: Research paper
Issue: 2006 Volume 1, no.1
Pages: 73-76
Keywords: copper (2+); d-f complexes; Schiff base; magnetic properties.
Full Text (PDF): Download
Abstract (JPEG)

DOI:
dx.doi.org/10.19261/cjm.2006.01(1).11

Graphical Abstract:
 The complexes of general formula Cu(H2L) (II); [CuLn(L)(NO3)(H2O)n] (where H4L=N,NI-bis[2- hydroxy(3-
carboxynaphtalidene)]ethylenediamine; Ln: Nd, n=6 (III); Eu, n=4 (IV); Gd, n=6 (V) have been synthesized a
nd investigated by different methods (IR spectroscopy, TG analysis and magnetochemistry). The coordination set of complex generators are Cu(N2O2) and Ln(O8-9). The effective magnetic moment values, μeff, at 300 K are: 1.78 (II), 3.22 (III), 6.44 (V) B.M. The temperature dependence (300-2 K) of magnetic susceptibility of [CuNd(L)(NO3)(H2O)6] indicates the antiferromagnetic interaction between metal ions.

Downloads: 24