Magnetic and ferroelectric properties of two Co(II) complexes based on flexible bis(imidazole) ligands

Two Co(II) complexes, [Co(bimb)(L1)2] (1) and [Co(bix)(L2)] (2) (bimb = 1,4-bis(imidazol-1–yl)-butane, bix = 1,4-bis(imidazol-1-yl-methylene)-benzene, HL1 = 3,5-dinitro-benzoic acid, H2L2 = o-phthalic acid), have been successfully prepared based on achiral flexible bis(imidazole) ligands via spontaneous resolution. Complexes 1 and 2 crystallize in the asymmetrical monoclinic with P21 and Cc space groups, respectively. Interestingly, magnetic studies reveal that complex 1 demonstrates dominant ferromagnetic behavior and complex 2 displays spin-canting behavior. More interestingly, both complexes 1 and 2 exhibit ferroelectric features representing electric hysteresis loops with the saturation polarization (Ps) of ca. 0.085 μC cm− 2 and 0.141 μC cm− 2.

This work reported two complexes based on flexible bis(imidazole) ligands with aromatic carboxylate ligands. And the focus on their magnetic and ferroelectric properties has been investigated in detail.Figure optionsDownload as PowerPoint slideHighlights
► Two complexes based on flexible bis(imidazole) ligands have been presented.
► Both ferromagnetic and ferroelectric behaviors were observed for complex 1.
► Spin-canting and ferroelectric behaviors were observed for complex 2.