Reactions of manganese acetate and lanthanide acetate with Schiff-base ligands (H3beemp = 2,6-bis[((2-(2-hydroxyethoxy)ethyl)imino)methyl]-4-methylphenol) yielded hexanuclear clusters of [View the MathML source(μ3-O)2(Hbeemp)2(OAc)8(μ3-OMe)2(H2O)2] · C8H17OH (Ln = Gd, Tb, and Y for 1, 2, and 3, respectively). Magnetic susceptibility measurements revealed that the mixed spin systems of 1 and 2 showed ferrimagnetic behavior, while antiferromagnetic interactions were operative among Mn3+ ions in 3. Ac magnetic susceptibility measurements for 2 showed frequency dependent in- and out-of-phase signals, confirming slow magnetic relaxation of spin reorientations.