Two novel Ni(II) complexes with polycatenated networks: Structures and magnetic properties

Abstract

Two nickel coordination polymers formulated as [Ni2(bpe)3(nip)2]n (1) and {[Ni(bpmp)(nip)(H2O)]·3H2O}n (2) (where H2nip=5-nitroisophthalic acid, bpe=1,2-bis-(4-pyridyl) ethane and bpmp=N,N′-bis-(4-pyridyl-methyl) piperazine) have been synthesized under hydrothermal condition. Single crystal X-ray diffraction analyses reveal that complex 1 presents a novel three-dimensional (3D) parallel polycatenated framework assembled from two-dimensional bilayers with cuboids as the fundamental building units. Compound 2 shows unusual 2D→3D inclined polycatenated framework consisting of two sets of equivalent 2D sql layers. The compounds have also been characterized by infrared spectra, elemental analysis, thermogravimetric analysis and powder X-ray diffraction. Magnetic studies reveal that these two compounds show similar antiferromagnetic interaction between Ni(II) ions.