Three different types of polynuclear manganese(II) compounds with chlorobenzoato bridges were obtained from the reaction of Mn(n-ClC 6 H 4 COO) 2 with 1,10-phenanthroline (phen): three trinuclear compounds [Mn 3 (µ-n-ClC 6 H 4 COO) 6 -(phen) 2 ] with n = 2, 3, 4 (1-3), one one-dimensional system [Mn(µ-3-ClC 6 H 4 COO) 2 (phen)] n (4) and one neutral dinuclear compound [{Mn(4-ClC 6 H 4 COO)(phen)} 2 (µ-4-ClC 6 H 4 COO) 2 -(µ-H 2 O)] (5). Compounds 1, 3, 4 and 5 were characterized by X-ray diffraction and show four different coordination modes for the carboxylate ligand: as a bidentate bridge in a syn-syn mode or syn-anti mode, as a monodentate bridge and as a terminal monodentate ligand. The five compounds show weak antiferromagnetic coupling; the J values are -2