A family of 3d-4f heterometallic compounds [Na(2)Fe(III)(6)Dy(III)(2)(N(3))(4)(HL)(4)(CH(3)O)(4)(PhCO(2))(6)] (1, H(4)L = 2-{[(2-hydroxy-3-methoxyphenyl)methylene]amino}-2-(hydroxymethyl)-1,3-propanediol), [Na(2)Fe(III)(6)Dy(III)(2)(N(3))(4)(L')(4)(CH(3)O)(4)(PhCO(2))(6)(H(2)O)] (2, H(3)L' = (E)-2-ethyl-2-(2-hydroxy-3-methoxybenzylideneamino)propane-1,3-diol), [Na(2)Fe(III)(6)Dy(III)(2)(N(3))(4)(L')(4)(CH(3)O)(4)(Bu(t)CO(2))(6)] (3) [Na(2)Fe(III)(6)Y(III)(2)(N(3))(4)(L')(4)(CH(3)O)(4)(PhCO(2))(6)(H(2)O)] (4), and [Na(2)Fe(III)(6)Gd(III)(2)(N(3))(4)(L')(4)(CH(3)O)(4)(PhCO(2))(6)(CH(3)OH)(2)] (5) have been prepared using Schiff-base ligands, trinuclear iron precursor complexes, azides and lanthanide nitrates as reactants. In compounds 1 and 2, the structure of the [Na(2)Fe(III)(6)Dy(III)(2)] cluster forms a couple of cis,trans-isomers with substitution of methyl for a free hydroxyl group which belongs to the Schiff-base ligand. When the pivalates are employed instead of bulkier benzoates, the trans-[Na(2)Fe(III)(6)Dy(III)(2)] clusters act as network nodes in the formation of rhombic grid-like layered structures in compound 2. Compounds 2, 4 and 5 have similar metallic cores, only with different crystal solvent molecules. The magnetic measurements on all the compounds indicate dominant antiferromagnetic interactions between the metal centers.