Formation of polynuclear iron(III) complexes of N-(2-pyridylmethyl)iminodipropanol depending on pseudohalide ions: synthesis, crystal structure, and magnetic properties

•Multinuclear iron(III) coordination complexes that have structural geometries depending on pseudohalide ions were synthesized.•In the cases of NCSe– and NCBH3–, dimeric structures are formed, whereas in the cases of N3– and NCO–, hexameric complexes are formed.•As using NCS- ion, the bent trimeric complex is obtained.•Dimeric and trimeric complexes show moderate antiferromagnetic interactions, whereas, hexameric complexes show both ferromagnetic and antiferromagnetic couplings.