2. Articole
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Item Heterometallic compounds with the binuclear complex anion [Cr 2(OH)(Ac)(Nta)2]2-: Synthesis and structure [Articol](2009) Ciornea, Victor; Șova, Sergiu; Novițchi, Ghenadie; Ganju, Dumitru; Cajeva, Olga; Gulea, Aurelian; Simonov, IurieHeterometallic compounds BaCr2(OH)(Ac)(Nta)2 • 4H2O (I) and [Fe(L)3][Cr2(OH)(Ac)(Nta) 2] • nH2O (L is Bipy (II) and Phen (III); Bipy is, αα′-bipyridine, Phen is o,o′-phenanthroline, Ac - is acetate ion, Nta is nitrilotriacetate ion; n = 8 (II) and 6.25 (III)) are synthesized. According to the X-ray diffraction data, compounds II and III have ionic structures built of the isolated complex cations [Fe(L) 3]2+, binuclear complex anions [Cr2(OH)(Ac) (Nta)2]2-, and crystallization water molecules. The magnetic properties of compounds II and III in the interval from 2 to 300 K confirm assumptions on the diamagnetic character of [Fe(L)3] 2+ and indicate the antiferromagnetic interaction between the chromium atoms in the dimeric fragment [Cr2(OH)(Ac)(Nta) 2]2-.Item Magnetic investigation of an unusual dissymmetric binuclear manganese carboxylate complex [Articol](2006) Novițchi, Ghenadie; Costes, Jean-Pierre; Popovschi, Lilia; Șova, Sergiu; Gulea, AurelianThe 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 S1S2ur ur, indicate that an antiferromagnetic interaction equal to J = -0.90(1) cm-1 is present. A correlation between J values and Mn-H2 O-Mn angles has been tempted.Item Structural, morphological and magnetic characterization of metal-chitosan/poly (vinyl amine) complexes [Articol](Springer Nature, 2017) Cocarta, Ana; Gutanu, Vasile; Dragan, EcaterinaCu and Ni complexes of chitosan/poly(vinyl amine) (CS/PVAm) composites were prepared. The metal-CS/PVAm complexes were characterized by FT-IR spectroscopy, SEM-EDX, X-ray diffraction (XRD), and magnetic moment determination. FT-IR spectra of the metal-CS/PVAm complexes showed the characteristic bands of anhidroglucose unit were affected by the metal complexation, and new bands assigned to Me-N and Me-O bonds were observed. SEM images of the surface of metal-composite complexes show the influence of metal ion on the morphology of the complexes, the strong binding of Cu and Ni, involving most of the amino groups, leading to a dense surface structure. The chemical composition on the surface of metal-CS/PVAm complexes was determined from EDX measurements. XRD provided information about the amorphous or crystalline nature of the composite and metal-composite complexes. Using magnetic susceptibility method, the oxidation degree of metal ions from the polymer phase, the homogeneous distribution of the ligand groups from the volume of the CS/PVAm beads, and the existence of the antiferromagnetic interactions between the metal ions were determined.Item Mixed-ligands μ3-oxo trinuclear carboxylates [Fe3O(CH2BrCOO)1.5(CH2ClCOO)4.5(H2O)3]Br0.75Cl0.25 5H2O and [Fe3O(BrCH2COO)6(H2O)3] NO3⋅2.63H2O [Articol](Academia de Știinițe a Moldovei, 2008) Shova, Sergiu; Lazarescu, Ana; Gdaniec, Maria; Simonov, Yurii; Turta, ConstantinTwo novel μ3-oxo-centered carboxylate-bridged triiron complexes [Fe3O(BrCH2COO)6(H2O)3]NO3·2.63H2O (1) and Fe3O(CH2BrCOO)1.5(CH2ClCOO)4.5(H2O)3]Br0.75Cl0.25 5H2O (2) were synthesized and their structures were characterized by X-ray crystallography. The opportunity of mixed-ligand complex formation in iron(III)-bromoacetic acid system was shown. The fi rst co-ordination sphere of the iron atom in compound 2 includes two different carboxylate anions, CH2BrCOO- and CH2ClCOO- in the capacity of syn-syn- bidentate-bridged ligands, while Br- and Cl- anions being in the ratio 1:1, formulate the external sphere of the complex. The IR spectra, thermic analysis and magnetic properties of complexes were studied.Item Magnetic investigation of an unusual dissymmetric binuclear manganese carboxylate complex [Articol](Academia de Știinițe a Moldovei, 2006) Novitchi, Ghenadie; Costes, Jean-Pierre; Popovschi, Lilia; Shova, Sergiu; Gulea, AurelianThe magnetic susceptibility (χT) of an unusual dissymmetric binuclear manganese corboxylate complex has been measured from 2 to 300K. The magnetic data which have been fted with help of the Heisenberg Dirac Van Vleck HDVV spin-exchange HamiltonianItem Sinteza, structura şi proprietăţile compuşilor coordinativi ai fierului cu 4-Feniltiosemicarbazona şi 4-Fenil-s-metiltiosemicarbazona 2-Acetilpiridinei [Articol](CEP USM, 2016) Palamarciuc, Tatiana; Sîrbu, Angela; Palamarciuc, OlegÎn acest articol este realizată sinteza compuşilor Fe(III) cu 4-feniltiosemicarbazona şi 4-fenil-S-metiltiosemicarbazona 2-acetilpiridinei, fiind propus studiul cristalografic şi magnetic al acestor compuşi cât şi studiul spectrofotometric în soluţie pentru ionii Fe(II) cu aceiaşi liganzi. Compuşii coordinativi [Fe(L1)2]BF4•CH3OH (1) şi [Fe(L2)2]FeCl4(2) au fost obţinuţi în soluţii alcoolice. Analiza cu raze X relevăfaptul cămetilarea atomului de sulf influenţează asupra modului de coordinare a liganzilor la ionul de Fe(III). Compuşii 1şi 2 manifestă proprietăţi magnetice diferite.Item Magnetic investigation of an unusual dissymmetric binuclear manganese carboxylate complex [Articol](Institute of Chemistry of ASM, 2006) Novitchi, Ghenadie; Costes, Jean-Pierre; Popovschi, Lilia; Shova, Sergiu; Gulea, AurelianThe 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 HJSS=−urur, indicate that an antiferromagnetic interaction equalto J = 0.90(1) cm-1 ispresent. A correlation between J values andMn-H2O-Mn angles has been tempted.