عنوان
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Tetranuclear Manganese(II) Complexes of Hydrazone and Carbohydrazone Ligands: Synthesis, Crystal Structures, Magnetic Properties, Hirshfeld Surface Analysis and DFT Calculations
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چکیده
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The complexes [Mn4(L1)4(N3)4] (1), [Mn4(L2)4(l-N3)2(N3)2(OCH3)2] (2) and [Mn4(l-L3)4(NCS)4]6CH3OH
(3) [L1 = N-1-(pyridin-2-yl)ethylidenepicolinohydrazonate, L2 = N-phenyl(pyridin-2-yl)methylenepicolino
hydrazonate, and L3 = ((phenyl(pyridin-2-yl)methylene)hydrazinyl)((Z)-2-(phenyl(pyridin-2-yl)
methylene)hydrazinyl)methanolate] have been synthesized, and their structures characterized. The
structures of 1 and 3 can be described as tetranuclear and are formed from four Mn(II) ions bridged by
four ligands. Complex 2 exhibits a centrosymmetric tetranuclear structure with two types of Mn(II) centers
with double end-on (EO) azido bridges. All the complexes have similar magnetic behavior and exhibit
weak intramolecular antiferromagnetic coupling, which is consistent with the oxygen-bridged square
structures with large Mn–O–Mn bridge angles. Theoretically obtained J values of 1.7 cm1 (for 1),
0.7 cm1 (for 2) and 3.3 cm1 (for 3) corroborate well the experimental results. Moreover, a
Hirshfeld surface (HS) analysis was employed to gain additional insight into interactions responsible
for packing of complexes 1–3 (with dnorm and shape-index functions). Quantitative examination of 2D fingerprint
plots revealed, amongst others, the dominating participation of H H and H C interactions in
the molecular packing.
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