A series of heterometallic Ln-Cr clusters with the formulas [Ln(5)Cr(2)(H2L)(2)(OAc)(6)(mu(3)-OH)(6)(H2O)(15)](ClO4)(7)center dot xH(2)O (Ln = Gd and x = 33 for 1 and Ln = Dy and x = 21 for 2) and [Ln(8)Cr(4)(H2L)(4)(OAc)(8)(mu(3)-OH)(16)(mu(4)-O)(1)(H2O)(8)](Cl)(ClO4)(5)center dot 10H(2)O (Ln = Gd for 3 and Ln = Dy for 4) was obtained through the reaction of the acetate ligands 2,2-dimethylolpropionic acid (H3L) and Ln(ClO4)(3) in the presence of chromium salts with different anions under the same high pH conditions. X-ray analysis revealed that compound 1 contained a metal unit [Gd3Cr2] displaying the pentagonal bipyramid configuration and that compound 3 was templated by Cl- and ClO4- as a mixed anion template featuring a quadrangular structure. In compound 3, the 12 metal atoms were arranged in a wheel-shaped metal skeleton [Gd8Cr4], which was produced by 4 tetrahedral metal units [Gd3Cr] sharing vertices. The introduction of the mixed anion template increased the number of metal atoms in the Ln-Cr clusters. Magnetic calculations indicated that there was weak antiferromagnetic Gd center dot center dot center dot Cr coupling and weak ferromagnetic Gd center dot center dot center dot Gd coupling in 1, whereas both Gd center dot center dot center dot Cr and Gd center dot center dot center dot Gd in 3 exhibited weak antiferromagnetic interactions. Magnetothermal studies showed that compounds 1 and 3 displayed magnetic entropy changes of 25.2 J kg(-1) K-1 at 5 K and 7 T and 33.8 J kg(-1) K-1 at 2 K and 7 T, respectively.