A novel magnetically coupled nonamanganese(II) 3 × 3 portcullis-like grid involving just oxygen bridges, generated by strict self assembly of the metal cation and a single heptadentate ligand

The heptadentate ligand 2POAP combines two bridging alkoxide oxygen donors with diazine and pyridine terminal nitrogen donors in a linear array with the binding sites positioned critically to accommodate three metal centres, but on reaction with Mn(ClO4)2·6H2O a strict self assembly process occurs, producing a unique homoleptic nonamanganese ‘square’ grid complex, involving six ligands.