Magnetic couplings mediated through the non-covalent interactions
Abstract
Density functional theory (DFT), broken symmetry (BS) approach, was applied in order to determine the mechanism of couplings through the non-covalent interactions for the series of coordination compounds bridged by strong hydrogen bonds, namely [Mn(F)(4)HF2](2-), [Ni(HF2)(pyz)(2)](-), [Cu(HF2)(pyz)(2)](-), [Cu2F(HF)(HF2)(pyz)(4)](2-), [CuF2(H2O)(2)(pyz)] (where pyz = pyrazine), [Cu-2(php)(2)(H2O)(2)](2+) (php = 6-(pyridine-2-ylhydrazonomethyl)phenol), [Cu(L-1)(H2O)](+) (HL1 = 1-(2-hydroxyethylaminomethyl)-3-hydroxyethyl-1,3-diazacyclohexane), multi copper active centers from Escherichia coli multi-copper oxidase and peptidylglycine alpha-hydroxylating monooxygenase, and [CuBr4](2-). In most investigated structures, main function of hydrogen bonds is to achieve reasonable distances between the interacting units, which are necessary for the favorable superexchange interactions. Antiferromagnetic couplings in Cu(II) complexes decrease with increasing distance between two monomer units. Th...is work can help in rational design of new materials with this kind of bridging ligands.
Keywords:
DFT / Binuclear complexes / Magnetic couplings / Broken symmetrySource:
Polyhedron, 2012, 42, 1, 89-94Publisher:
- Pergamon-Elsevier Science Ltd, Oxford
Projects:
DOI: 10.1016/j.poly.2012.04.040
ISSN: 0277-5387