A family of manganese complexes, [Mn5O3(t-BuPO3)(2)(MeCOO)(5)(H2O)(phen)(2)] (1), [Mn5O3(t-BuPO3)(2)(PhCOO)(5)(phen)(2)] (2), [Mn4O2(t-BuPO3)(2)(RCOO)(4)(bpy)(2)] (R = Me, (3); R = Ph, (4)), NBu4n[Mn4O2(EtCOO)(3)(MeCOO)(4)(pic)(2)] (5), NR'(4)[Mn4O2(i-PrCOO)(7)(pic)(2)] (R' = Bu-n, (6); R' = Et, (7)), were synthesized and characterized. The seven manganese clusters were all prepared from a reaction system containing tert-butylphosphonic acid, Mn(O2CR)(2) (R = Me, Ph) and NR'4MnO4 (R' = Bu-n, Et) with similar procedures except for using different N-containing ligands (1,10-phenanthroline (phen), 2,2'-bipyridine (bpy) and picolinic acid (picH)) as coligands. The structures of these complexes vary with the N-containing donors. Both the cores of complexes 1 and 2 feature three mu(3)-O and two capping t-BuPO32- groups bridging five Mn-III atoms to form a basket-like cage structure. Complexes 3 and 4 both have one [Mn-4(mu(3)-O)(2)](8+) core with four coplanar Mn-III atoms disposed in an extended "butterfly-like" arrangement and two capping mu(3)-t-BuPO32- binding to three manganese centers above and below the Mn-4 plane. Complexes 5, 6, and 7 all possess one [Mn-4(mu(3)-O)(2)](8+) core just as complexes 3 and 4, but they display a folded "butterfly-like" conformation with the four Mn-III atoms nonplanar. Thus, the seven compounds are classified into three types, and three representative compounds 1 center dot 2H(2)O center dot MeOH center dot MeCN, 3 center dot 6H(2)O center dot 2MeCOOH, and 5 center dot 0.5H(2)O have been characterized by IR spectroscopy, ESI-MS spectroscopy, magnetic measurements and in situ UV-vis-NIR spectroelectrochemical analysis. Magnetic susceptibility measurements reveal the existence of both ferromagnetic and antiferromagnetic interactions between the adjacent Mn-III ions in compound 1 center dot 2H(2)O center dot MeOH center dot MeCN, and antiferromagnetic interactions in 3 center dot 6H20 center dot 2MeCOOH and 5 center dot 0.5H(2)O. Fitting the experimental data led to the following parameters: J(1) = -2.18 cm(-1), J(2) = 6.93 cm(-1), J(3) = -13.94 cm(-1), J(4) = -9.62 cm(-1), J(5) = -11.17 cm(-1), g = 2.00 (1 center dot 2H(2)O center dot MeOH center dot MeCN), J(1) = -5.41 cm(-1), J(2) = -35.44 cm(-1), g = 2.13, zJ = -1.55 cm(-1) (3 center dot 6H(2)O-2MeCOOH) and J(1) = -2.29 cm(-1), J(2) = -35.21 cm(-1), g = 2.02, zJ -0.86 cm(-1) (5 center dot 0.5H(2)O).