Field-Induced Ferromagnetism and Multiferroic Behavior in End-on Pseudohalide-Bridged Dinuclear Copper(II) Complexes with Tridentate Schiff Base Blocking Ligands

Abstract

Four new end-on pseudohalide-bridged dinuclear copper(II) complexes, [Cu2(L(1))2(N3)2]·DMF (1), [Cu2(L(2))2(N3)2] (2), [Cu2(L(3))2(NCS)2] (3), and [Cu2(L(4))2(N3)2] (4) {where HL(1), HL(2), HL(3), and HL(4) are tridentate N2O donor Schiff bases}, are synthesized and characterized. Complexes 1, 2, and 3 possess π···π stacking interactions, while in addition hydrogen-bonding interactions are present in 1 and 3. However, by contrast, complex 4 contains neither type of interaction. Field-induced long-range ferromagnetic ordering beyond 0.9 T is observed in complexes 1 and 2 due to π···π stacking interactions, while ferroelectric ordering is observed in complexes 1 and 3 due to hydrogen-bonding interactions. Most interestingly, complex 1, which contains both π···π stacking and hydrogen-bonding interactions, shows multiferroic behavior as a result of coupling between the dielectric and magnetic fields with 8% change in the magneto-dielectric effect at room temperature. We believe that from this study will emerge a new class of multiferroic materials.

Mono, di and trinuclear photo-luminescent cadmium(II) complexes with N2O and N2O2 donor salicylidimine Schiff bases: Synthesis, structure and self assembly

“…S1) with the symmetry related phenoxo oxygen atom, O(1) a , {Symmetry transformation, a = x, 1/2 À y, 1 À z} of a neighbouring molecule. This is a very strong H bond (DonorÁ Á ÁAcceptor distance 2.45 Å) with respect the other reported systems [15,28,47]. Selected bond angles are gathered in Table S1.…”

“…Among different Schiff bases, N 2 O donor salicylidimine Schiff bases [11][12][13], have widely been used by several groups to form different homo and hetero polynuclear complexes with several transition and non-transition metal ions [14][15][16][17][18][19][20]. On the other hand, there have been immense interests in studying supra-molecular structures [21].…”

Chirality‐Induced Variation in Interaction of Two Similar Copper(II) Coordination Polymers with Calf Thymus DNA: Exploration of Their Antimicrobial Activity and Cytotoxicity

“…The N 2 O donor Schiff bases (HL 1 and HL 2 ) have been prepared by the 1:1 condensation of 2‐hydroxy‐1‐acetonaphthone with N,N ‐diethyl‐1,2‐diaminoethane and N,N ‐dimethyl‐1,2‐diaminoethane respectively in methanol following the literature method . HL 1 and HL 2 on reaction with copper(II) acetate monohydrate followed by the addition of sodium dicyanamide give chains of [Cu(L 1 )(μ 1,5 ‐dca)] n ( 1 ) and [Cu(L 2 )(μ 1,5 ‐dca)] n ( 2 ) respectively.…”

A polynuclear and two dinuclear copper(II) Schiff base complexes: Synthesis, characterization, self-assembly, magnetic property and DFT study

“…On the other hand, due to the absence of any meaningful overlap between magnetic orbitals, basalapical bridges usually give rise to very small magnetic couplings for end on modes [24][25][26][27][28][29][30][31]. Same is the case for the end to end dca bridged complexes due to relatively longer distance between the copper(II) centres [32][33].…”