Synthesis, Structures, and Magnetic Properties of Novel Mononuclear, Tetranuclear, and 1D Chain MnIII Complexes Involving Three Related Asymmetrical Trianionic Ligands
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- 作者：Jean-Pierre Costes ; Franç ; oise Dahan ; Bruno Donnadieu ; Maria-Jesus Rodriguez Douton ; Maria-Isabel Fernandez Garcia ; Azzedine Bousseksou ; and Jean-Pierre Tuchagues
- 刊名：Inorganic Chemistry
- 出版年：2004
- 出版时间：April 19, 2004
- 年：2004
- 卷：43
- 期：8
- 页码：2736 - 2744
- 全文大小：172K
- 年卷期：v.43,no.8(April 19, 2004)
- ISSN：1520-510X
文摘
The manganese(III) complexes studied in this report derive from asymmetrical trianionic ligands abbreviated H3Li(i = 4-6). These ligands are obtained through reaction of salicylaldehyde with "half-units", the latter resulting frommonocondensation of different diamines with phenylsalicylate,. Upon deprotonation, Li (i = 4-6) possess an innerN2O2 coordination site with one amido, one imine, and two phenoxo functions, and an outer amido oxygen donor.The trianionic character of such ligands yields original neutral complexes with the L/Mn stoichiometry. The crystaland molecular structures of three complexes have been determined at 190 K (1) or 180 K (2 and 3). Complex 1crystallizes in the triclinic space group P
(No. 2): a = 7.8582(14) Å, b = 10.9225(16) Å, c = 12.4882(18) Å, 
= 67.231(14)
, 
= 72.134(14), 
= 82.589(13), V = 940.6(3) Å3, Z = 2. Complex 2 crystallizes in theorthorhombic space group Pbcn (
. 60): a = 23.8283(15) Å, b = 11.1605(7) Å, c = 26.152(2) Å, V = 6954.8(8) Å3, Z = 8, while complex 3 crystallizes in the monoclinic space group P21/c (No. 14) with a = 11.7443(14) Å,b = 7.5996(10) Å, c = 18.029(2) Å, = 100.604(10), V = 1581.6(3) Å3, Z = 4. Owing to hydrogen bonds and
- stackings, the mononuclear neutral molecules of 1 are arranged in a 2D network while complexes 2 and 3are tetranuclear and polymeric (1D chain) species, respectively, owing to the bridging ability of the oxygen atomof the amido function. The experimental magnetic susceptibilities of complexes 2 and 3 indicate the occurrence ofsimilarly weak MnIII-MnIII antiferromagnetic interactions (J = -1.1 cm-1). Single ion zero-field splitting of manganese(III) must be taken into account for satisfactorily fitting the data by exact calculation of the energy levels associatedto the spin Hamiltonian through diagonalization of the full matrix for axial symmetry in 2 (J = - 1.1 cm-1, D1 =2.2 cm-1, D2 = -2.8 cm-1), D1 and D2 being associated to the six- and five-coordinate Mn ions, respectively. Aweaker antiferromagnetic interaction (J = - 0.2 cm-1) operates through - stacking in complex 1. Complex 3is a weak ferromagnet (ordering temperature ~7 K) as a result of the spin canting originating from the crystalpacking.
(No. 2): a = 7.8582(14) Å, b = 10.9225(16) Å, c = 12.4882(18) Å, = 67.231(14), = 72.134(14), = 82.589(13), V = 940.6(3) Å3, Z = 2. Complex 2 crystallizes in theorthorhombic space group Pbcn (. 60): a = 23.8283(15) Å, b = 11.1605(7) Å, c = 26.152(2) Å, V = 6954.8(8) Å3, Z = 8, while complex 3 crystallizes in the monoclinic space group P21/c (No. 14) with a = 11.7443(14) Å,b = 7.5996(10) Å, c = 18.029(2) Å, = 100.604(10), V = 1581.6(3) Å3, Z = 4. Owing to hydrogen bonds and- stackings, the mononuclear neutral molecules of 1 are arranged in a 2D network while complexes 2 and 3are tetranuclear and polymeric (1D chain) species, respectively, owing to the bridging ability of the oxygen atomof the amido function. The experimental magnetic susceptibilities of complexes 2 and 3 indicate the occurrence ofsimilarly weak MnIII-MnIII antiferromagnetic interactions (J = -1.1 cm-1). Single ion zero-field splitting of manganese(III) must be taken into account for satisfactorily fitting the data by exact calculation of the energy levels associatedto the spin Hamiltonian through diagonalization of the full matrix for axial symmetry in 2 (J = - 1.1 cm-1, D1 =2.2 cm-1, D2 = -2.8 cm-1), D1 and D2 being associated to the six- and five-coordinate Mn ions, respectively. Aweaker antiferromagnetic interaction (J = - 0.2 cm-1) operates through - stacking in complex 1. Complex 3is a weak ferromagnet (ordering temperature ~7 K) as a result of the spin canting originating from the crystalpacking.