A new family of hexametallic [MnIII6] Single-Molecule Magnets with general formula [Mn6O2(R-sao) 6(X)2(MeOH)4-6] (R = H, Me, Et or Ph; X = O2PHPh or O2P(Ph)2) have been synthesised and characterised. The molecules are new members of the [Mn6] family of SMMs in which the carboxylate ligands have been replaced with phenyl- and diphenylphosphinate. The magnetic cores remain largely unaltered meaning that structural distortions of the Mn-N-O-Mn torsion angles in the [Mn3O] subunits can be used to tune the magnetic properties, switching pairwise exchange interactions from antiferromagnetic to ferromagnetic. The results suggest that the Mn6 building block, be it ferro- or antiferromagnetically coupled, could be an important building block for the formation of novel, functional 0-3D materials. © The Royal Society of Chemistry 2010.