Open and closed copper chain coordination polymers with alternating ferromagnetic and antiferromagnetic interactions

Abstract

Two copper(II) coordination polymers formulated {[Cu3(HL)2(MeOH)2(H2O)2]·2H2O}n (1) and {[Cu4(L)2(H2O)8]·5H2O}n (2) were obtained utilizing the polycarboxylate ligand 2-(bis(carboxymethyl)amino)terephthalic acid (H4L) and characterized by X-ray diffraction, FT-IR spectra, elemental analysis and EPR spectra. 1 crystallizes in P21/c space group and shows a closed 1D double zigzag chain composed of trinuclear building block [Cu3(HL)2(H2O)4]. 2 crystallizes in a chiral space groupP21 and exhibits an open chain structure with tetranuclear building block [Cu4(L)2(H2O)8]. Fitting the variable-temperature magnetic susceptibilities of two compounds gave g = 2.16, J = 4.25 cm−1, zJ′ = −0.88 cm−1 for 1, and g = 2.13, J1 = −2.61 cm−1, J2 = 2.97 cm−1, zJ′ = −0.12 cm−1 for 2, respectively, indicating the alternating ferromagnetic and antiferromagnetic interactions.