The syntheses, structures, and magnetic properties are reported for three new Ce/Mn clusters with different Ce/Mn ratios: [Ce6Mn4O12(O2CMe)(10)-(NO3)(4)(py)(4)] (py = pyridine) (1), [CeMn8O8(O(2)CCH(2)tBu)(12)(DMF)(14)] (DMF = dimethylformamide) (2), and [Ce2Mn4O2(O2CMe)(6)(NO3)(4)(hmp)(4)] (3; hmp(-) is the anion of 2-(hydroxymethyppyridine). 1 and 2 were obtained from the reaction of Ce(IV)with [Mn12O12(O2CMe)(16)(H2O)(4)] ((Mn8Mn4IV)-Mn-III) and [Mn8O2(O-2-CCH213u),4(tBuCH(2)CO(2)H)(4)] ((Mn6Mn2III)-Mn-II), respectively, whereas 3 resulted from the oxidation of Mn-II acetate with Ce-IV in the presence of hmpH. Cluster 1 possesses an unusual [Ce6Mn4O12](14+) core topology consisting of a [Ce6O8] face-capped octahedron, which is face-fused at each end to a [(Ce2MnMnO4)-Mn-IV-Mn-III-O-IV] cubane. Cluster 2 possesses a nonplanar, saddlelike loop of eight Mn-II atoms bridged by eight mu(3)-O2- ions to a central Ce-IV atom. Cluster 3 is similar to 1 in possessing an octahedral core, but this is now a [Ce2Mn4] octahedron consisting of a Ce-III atom on either side of a Mn-4, parallelogram, with the metal atoms bridged by two mu(4)-O2- ions, the alkoxide arms of four hmp- groups, and six acetates. Clusters 1, 2, and 3 are thus at the (Ce6Mn2Mn2IV)-Mn-IV-Mn-III, Ce-IV Mn-III, and (Ce2Mn4III)-Mn-III oxidation levels, respectively. Variable-temperature, solid-state direct current (DC) and alternating current (AC) magnetization studies on 1-3 in the 5.0-300 K range revealed predominantly antiferromagnetic exchange interactions within the complexes. For 1, fitting of the DC data to the theoretical expression for a dinuclear (MnMnIV)-Mn-III complex derived using the Van Vleck equation and an isotropic spin Hamiltonian (K = 2J (S) over cap (i)center dot(S) over cap) convention) gave a value for the exchange coupling parameter (I) of 60.4(7) cm(-1) and a Lande factor g = 2.00(1), indicating an S = 1/2 ground state. For 2, both DC and AC data indicate an S = 0 ground state, which is unprecedented for a member of the CeMn8 family and now means members of the latter have been made that span the whole range of possible ground states from S = 0 to the maximum S = 16. Cluster 3 possesses an S = 0 ground state for its Mn4 fragment, with the paramagnetism remaining at low temperature coming from the weakly coupled Ce-III centers. These three species are new additions to the Mn-Ce family of clusters and the broader class of 3d/4f molecular systems.