Syntheses, X-ray Structures, Solid State High-Field Electron Paramagnetic Resonance, and Density-Functional Theory Investigations on Chloro and Aqua MnII Mononuclear Complexes with Amino-Pyridine Pentadentate Ligands.

The two pentadentate amino-pyridine ligands L25 and L35 (L25 and L35 stand for the N-methyl-N,N',N'-tris(2-pyridylmethyl)ethane-1,2-diamine and the N-methyl-N,N',N'-tris(2-pyridylmethyl)propane-1,3-diamine, resp.) were used to synthesize four mononuclear MnII complexes, [(L25)MnCl](PF6) (1(PF6)), [(L35)MnCl](PF6) (2(PF6)), [(L25)Mn(OH2)](BPh4)2 (3(BPh4)2), and [(L35)Mn(OH2)](BPh4)2 (4(BPh4)2). The x-ray diffraction studies revealed different configurations for the ligand L5n (n = 2, 3) depending on the 6th exogenous ligand and/or the counterion. Solid state high-field ESR spectra were recorded on complexes 1-4 as on previously described mononuclear MnII systems with tetra- or hexadentate amino-pyridine ligands. Pos. and neg. axial zero-field splitting (ZFS) parameters D were detd. whose abs. values ranged from 0.090 to 0.180 cm-1. D.-functional theory calcns. were performed unraveling that, in contrast with chloro systems, the spin-spin and spin-orbit coupling contributions to the D-parameter are comparable for mixed N,O-coordination sphere complexes. [on SciFinder(R)]

Références

Titre
Syntheses, X-ray Structures, Solid State High-Field Electron Paramagnetic Resonance, and Density-Functional Theory Investigations on Chloro and Aqua MnII Mononuclear Complexes with Amino-Pyridine Pentadentate Ligands.
Type de publication
Article de revue
Année de publication
2008
Revue
Inorg. Chem.
Volume
47
Pagination
9238–9247
ISSN
0020-1669
Soumis le 12 avril 2018