Hydrothermal Synthesis, Structures, and Magnetic Properties of Three Novel 5-Aminoisophthalic Acid Ligand Bridged Transition Metal Cation Polymers

Three novel 5-aminoisophthalic acid (AIP) bridged polymers [Co(C8NH5O4)(H2O)]n (1), [Ni(C8NH5O4)(H2O)2]n (2),
and [Zn(C8NH5O4)(H2O)]n (3) were synthesized by hydrothermal reactions and characterized by IR, Raman, elemental
analysis, ESR, and magnetic measurements. X-ray single-crystal analyses were carried out for [Co(C8NH5O4)(H2O)]n (1), which crystallizes in the triclinic system, space group P1̄, with a = 6.477(1) Å, b = 7.130(1) Å, c =
9.826(2) Å, α = 108.9(1)°, β = 93.97(3)°, γ = 98.82(3)°, and Z = 2; for [Ni(C8NH5O4)(H2O)2]n (2), in the triclinic
system, space group P1̄, a = 6.425(1) Å, b = 8.115(2) Å, c = 10.146(2) Å, α = 113.09(3)o, β = 99.64(3)o, γ
= 98.90(3)o, and Z = 2; and for [Zn(C8NH5O4)(H2O)]n (3), in the monoclinic system, space group P2(1)/n, a =
9.044(1) Å, b = 8.264(1) Å, c = 11.646(1) Å, β = 100.77(1)°, and Z = 4. The single X-ray diffraction studies
reveal that 1 consists of an infinite honeycomb layer formed by four crystallographically independent motifs packed
alternatively together; 2 consists of an infinite neutral railroad-like linear polymer, and 3 consists of infinite layers
of alternating four-coordinated Zn(II) cations and AIP ligands. Finally, they are all packed into beautiful three-dimensional frameworks through complicated hydrogen bonding. Antiferromagnetic and ferromagnetic behaviors
were observed for 1 and 2 from the magnetic measurements.