A novel magnetically coupled nonamanganese(II) 3 x 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 t he binding sites positioned critically to accommodate three metal centres, but on reaction with Mn(ClO4)(2). 6H(2)O a strict self assembly process occ urs, producing a unique homoleptic nonamanganese 'square' grid complex, inv olving six ligands.