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1

Zastosowanie teorii funkcjonałów gęstości do modelowania właściwości elektronowych skorpionianowych kompleksów oksodimolibdenowych

Romańczyk P., Brocławik E.

Chemik

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2011

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Vol. 65, nr 10

1093-1100

PL

W artykule, na przykładzie skorpionianowych kompleksów oksodimolibdenowych o mieszanej walencyjności, przedstawiono zastosowanie modelowania DFT do określenia i interpretacji fizycznej wpływu wzajemnej orientacji grup [MoII,INO]3+,2+ (par donorowo- akceptorowych, D-A) na przepływ gęstości elektronowej we fragmencie Mo-O-Mo. Zależność struktury elektronowej, tj. lokalizacji/ delokalizacji niesparowanego elektronu od wzajemnego położenia lokalnych układów współrzędnych D i A, może nadawać kompleksom właściwości molekularnych przełączników i reostatów.

EN

This paper presents the application of DFT modelling in the determination and physical interpretation of the effect of mutual orientation of [MoII, INO] 3+,2+ groups (donor-acceptor pairs, D-A) on the electron density flow in the Mo-O-Mo moiety, exemplified by oxodimolybdenum scorpionate complexes of mixed valence. The relationship between the electron structure, i.e. localization/ delocalization of unpaired electron and mutual position of D and A coordinate systems, may bestow the properties of molecular switches and rheostats on complexes.

2

Synthesis, Characterization and Antiferromagnetic Interaction in Oxalato-Bridged Chromium(III)-Chromium(III) Binuclear Complexes

Wang S., Li Y., Yan C.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 6

865-872

EN

Two new mi-oxalato-bridged binuclear chromium(III) complexes, [Cr2(ox)(salen)(bpy)2]- (NO3)2 (1) and [Cr2 (ox)(salen)(phen)2](NO3)2 (2) [where salen = N,N'-ethylenebis- (salicylideneiminate), ox = oxalato, bpy = 2,2'-bipyridine and phen = 1,10-phenanthroline], have been synthesized by the strategy of 'complex as ligand', and characterized by elemental analyses, molar conductance and magnetic moments of room-temperature measurements, and spectroscopic studies. It is proposed that the two complexes have extended ox-bridged structures consisting of two chromium(III) ions, each in an octahedral environment. The two complexeswere further characterized by variable temperature magnetic susceptibility (4.2~300 K) measurements and the observed data were successfully simulated by the equation based on the spin Hamiltonian operator, H= - 2JS S 1 2 giving the exchange integrals J = -2.78 cm-1 for (1) and J = -3.85 cm-1 for (2). This result indicates the presence of weak antiferromagnetic interaction between the metal ions within each molecule.

3

Synthesis and magnetic Studies of mi-Iodanilato-Bridged Iron(III)-Iron(III) Binuclear Complexes

Li Y., Yan C. -W., Guan H. -S.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 8

935-942

EN

Four new _-iodanilato-bridged binuclear iron(III) complexes have been prepared and identified: [Fe2(IA)L4](ClO4)4, where IA represents the dianion of iodanilic acid and L denotes 2,2_-bipyridine (bpy); 1,10-phenanthroline (phen), 5-chloro-1,10-phenanthroline (Cl-phen) or 5-nitro-1,10-phenanthroline (NO2-phen). Based on elemental analyses, molar conductivity, magnetic moment of room-temperature measurements, IR and electronic spectra studies, these complexes are proposed to have extended IA-bridged structures consisting of two iron(III) ions, each in a distorted octahedral environment. The complexes [Fe2(IA)(bpy)4](ClO4)4 (1) and [Fe2(IA)(phen)4](ClO4)4 (2) were further characterized by variable temperature (4.2~300 K) magnetic susceptibility measurements and the observed data were successfully simulated by the equation based on the spin Hamiltonian operator,_ _ _ H = 2JS S 1 2 Ĺ , giving the exchange parameter J = -6.9 cm-1 for (1) and J = -9.8 cm-1 for (2). These results are commensurate with antiferromagnetic spin-exchange interaction between the two iron(III) ions within each molecule. The influence of halogen substituents in the bridging ligand on magnetic interactions between the metal ions of this kind of complexes is also discussed.

4

Novel Ferromagnetic Coupling Dicopper(II), Antiferromagnetic Dicobalt(II) and Dimanganese(II) Complexes with 3-Nitro-phthalato as Bridging Ligand: Synthesis, Spectrum and Magnetism

Ma S. L., Zhang L. Z., Lu L. L., Tang M. Y.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 4

511-517

EN

Novel copper(II), cobalt(II) and manganese(II) binuclear complexes have been synthesized, namely [Cu2(3-NO2-phth)(phen)4](ClO4)2 and [M2(3-NO2-phth)(phen)4(H2O)2](ClO4)2, whereM=Co orMn, phen = 1,10-phenanthroline and 3-NO2-phth denotes 3-nitro-phthalate dianion. Magnetic susceptibility measurements between 4.2-300 K (or 77-300 K) demonstrate a ferromagnetic interaction between two copper(II) ions in the Cu-Cu complex, and a weak antiferromagnetic interaction between the metal ions in Co-Co and Mn-Mn complexes. Based on spin Hamiltonian operator, _H = -2J _ S1_ _ S2 (S1=S2 = 1/2, S1=S2 = 3/2 or S1 = S2 = 5/2), J is found to be equal to +5.26 cm-1, -1.72 cm-1 and -0.62 cm-1 for the Cu-Cu, Co-Co and Mn-Mn complexes, respectively

5

Synthesis, Characterization and Magnetic Properties of mi-Oxalato-Bridged Binuclear Iron(III) Complexes

Li Y. T., Yan C. W., Zhang Y. H.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 12

1825-1831

EN

Four new oxalato-bridged iron(FII)-iron(III) binuclear complexes have been synthesized and characterized, namely [Fe2(ox)jL2], where ox represents the oxalato dianions; L stands for 2,9-dimethyl-1,10-phenanthroline (Mc2-phen); 4,7-diphenyl-1,10-phenanthroline o:'"o (Ph2-phen); diaminoethane (en) or l ,3-diaminopropane (pn), respectively. Based on elemental analyses, molar conductivity and magnetic moment (at room-temperature) measurements, IR and electronic spectral studies, these complexes arę proposed to have extended ox-bridged structure consisting of two iron(IIl) ions, each in an octahedral environment. The variab!e-teinperature susceptibilities of [Fe2(ox)](Me2-phen)2] (1) and [Fe2(ox))(Ph2-phen)j] (2) complexes were measured and studied in the 4.2-300 K range. The magnetic coupling parameter is consistent with an antiferromagnetic exchange in-teraction between the iron(FFI) ions through the oxalato-bridged in both complexes (1) and (2). Based on the spin Hamiltonian operator, H = 2JS i -S 2, the exchange parameters (J) were evaluated as -4.85 cm"' for (I) and J = -6.39 crrf' for (2).

6

Synthesis, Characterization and Magnetic Analysis of Bromanilato-Bridged Binuclear Iron(II) Complexes

Li Y., Zeng X.

Polish Journal of Chemistry

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2000

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Vol. 74, nr 2

173-180

EN

Five new bromanilato-bridged binuclear iron(III) complexes have been synthesized and characterized, namely [fe(BA)L4](ClO4)4 where BA represents the dianion of bromanilic acid and L denotes 2,2'-bipyrydine (bpy); 1;10-phenanthroline (phen), 5-chloro-1,10-phenanthroline (Cl-phen), 5-bromo-1,10-phenanthroline (Br-phen) or 5-nitro-1,10-phenanthroline (NO2-phen). Based on elemental analyses, molar conductivity, magnetic moment of room-temperature measurements, IR and electronic spectra studies, these complexes are proposed to have extended BA-bridged structures consisting of two iron(III) ions, each in a distorted octahedral environment. The complexes [Fe2(BA)(bpy)4](ClO4)4 (1) and [Fe2(BA)(phen)4](ClO4)4 (2) were further characterized by variable temperature (4.2-300 K) magnetic susceptibility measurements and the observed data were successfully simulated by the equation based on the spin Hamiltonian operator, H=-2jS1*S2, giving the exchange parameter J=-3.6 cm-1 for (1) and J=-7.9 cm-1 for (2). These results are comensurate with weak antiferromagnetic spin-exchange interaction between the two Fe(III) ions within each molecule. The influence of halogen substituents in the bridging ligand on magnetic interactions between the metal ions of this kind of complexes is also discussed.

7

Synthesis and Magnetic Studies of M-Iodanilato-Bridged Binuclear Oxovanadium(IV) Complexes

Li Y., Yan C.

Polish Journal of Chemistry

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2000

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Vol. 74, nr 8

1071-1077

8

Synthesis and Ferromagnetic Spin-Coupling in N,N'-Oxamidobis(benzoato)cuprate(II) Bridged Copper(II)-Chromium(III) Heterobinuclear Complexes

Li Y., Yan C., Zeng X.

Polish Journal of Chemistry

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2000

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Vol. 74, nr 3

369-376