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A new family of isostructural 3d-4f polymetallic complexes,formulated as[Cu6Ln5(μ3-OH)9 (C4H8O2N)6(C5H4ON)6(H2O)9]·(ClO4)6·(H2O)22 (Ln =Pr,1;Nd,2;Sm,3;Eu,4;Gd,5),was successfully isolated through the simple hydrolysis reaction of 2-aminoisobutyric acid,2-hydroxypyridine,Cu(CH3COO)2·H2O,and Ln(ClO4)3·6H2O.Notably,the[Cu6Ln5]clusters with high molecular symmetry of D3h are rare examples of 2-aminoisobutyric acid-based 3d-4f clusters.The successful theoretical modeling of 5 yielded that the Gd-Gd exchange is of order 0.2 K,whereas the Gd-Cu exchange is an order of magnitude larger.Magnetization data collected for complex 5 yield a magnetic entropy change (-△Sm) of 19.6J kg-1 K-1 at 3 K and 7 T,which may be attributed to the weak magnetic interactions between the component metal ions.