Two tetranuclear 3d–4f complexes: Syntheses, structures and magnetic properties

• Two novel 3d–4f tetranuclear complexes have been synthesized and characterized.
• They display tetranuclear feature, while exhibiting diverse magnetic behaviors.
• The magnetic studies demonstrate slow magnetic relaxation processes for 2.

The solvothermal reactions of 3,5-bis(trifluoromethyl)benzoic acid (HL) and 2,2′-bipyridine (bipy) with the corresponding metal salts afforded two novel 3d–4f tetranuclear complexes M2Dy2(L)10(bipy)2 (M = Mn 1, Cu 2), which have been characterized by single-crystal X-ray diffraction, infrared spectroscopy, element analyses, powder X-ray diffraction and thermal gravimetric analyses. Complexes 1 crystallizes in the triclinic space group P-1, and the completely deprotonated L ligands possess μ2: η1, η1 and μ2: η2, η1 coordination modes to bridge adjacent metal ions which further connect into 2D layers by hydrogen bonds. Complex 2 crystallizes in the distinct monoclinic space group P21/c, and adjacent metal ions were linked by L ligands with the same coordinated patterns with 1, and supramolecular sheets were formed in the ab plane. Dynamic magnetic susceptibility studies reveal slow magnetic relaxation processes for 2, suggesting SMM type behavior.

Two novel 3d–4f tetranuclear complexes based on 3,5-bis(trifluoromethyl)benzoic acid have been solvothermal synthesized and characterized. They both exhibit tetranuclear structure feature, whereas crystallize in different space group and have various magnetic behavior. Complex 2 shows slow magnetic relaxation processes.Figure optionsDownload as PowerPoint slide