1 research outputs found
[1,2,4]Triazolo[4,3‑<i>a</i>]Pyridines as Bridging LigandsMagnetism of Azole-Bridged Dinuclear Copper(II) Complexes Influenced by the Trigonal Distortion Parameter τ
The
dinuclear doubly azole-bridged copper(II) complexes [Cu<sup>II</sup><sub>2</sub>(<b>L</b>)<sub>2</sub>(MeCN)<sub>4</sub>](ClO<sub>4</sub>)<sub>4</sub>·3.73MeCN·0.80H<sub>2</sub>O and [Cu<sup>II</sup><sub>2</sub>(<b>L</b>)<sub>6</sub>](ClO<sub>4</sub>)<sub>4</sub>·solvent (solvent = 2MeCN·H<sub>2</sub>O;
2MeCN·2H<sub>2</sub>O; 1.5MeOH·3.5H<sub>2</sub>O) were prepared
[<b>L</b> = 3-(6-methyl-2-pyridyl)-[1,2,4]triazolo[4,3-<i>a</i>]pyridine]. Structural characterizations revealed very
different local geometries about the copper(II) ions, being trigonal
bipyramidal for the former (τ = 0.76) and square pyramidal for
the latter (τ = 0.07, 0.15, 0.07) complex. Magnetic measurements
of bulk material [Cu<sup>II</sup><sub>2</sub>(<b>L</b>)<sub>2</sub>(H<sub>2</sub>O)<sub>4</sub>](ClO<sub>4</sub>)<sub>4</sub> and [Cu<sup>II</sup><sub>2</sub>(<b>L</b>)<sub>6</sub>](ClO<sub>4</sub>)<sub>4</sub>·2H<sub>2</sub>O revealed antiferromagnetic
coupling in both complexes, however, of very different strengths.
Electron paramagnetic resonance (EPR) spectroscopy was applied to
investigate magnetic properties of the complexes in detail. These
experimental findings were supported by broken-symmetry DFT calculations.
Systematic magneto-structural correlations are discussed