pH‐Controlled topologies of two Co(II) complexes based on 5‐Nitro‐1,2,3‐benzenetricarboxylic acid and 1,6‐Bis(1,2,4‐triazole‐1‐yl)hexane

Two new Co(II) coordination polymers, [Co(Hnbta)(bth)] n ( 1 ) and {[Co 3 (nbta) 2 (bth) 3 (H 2 O)]·H 2 O} n ( 2 ), (H 3 nbta = 5‐nitro‐1,2,3‐benzenetricarboxylic acid and bth = 1,6‐bis(1,2,4‐triazole‐1‐yl)hexane), have been synthesized under different pH values through hydrothermal reactions. Both complexes were characterized by elemental analysis, IR spectra, thermogravimetric analysis (TGA), and single‐crystal X‐ray crystallography. Complex 1 exhibits a 3D polythreaded network based on 4‐connected sql 2D layer. Complex 2 has a (4,4,5)‐connected trinodal 3D pillar‐layered network with a (4 2 ·6 4 ) 2 (4 2 ·6 7 ·8) 2 (6 4 ·8 2 ) topology. Magnetic susceptibility measurements indicate that complexes 1 and 2 show weak antiferromagnetic interactions between the adjacent Co(II) ions.