Abstract
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 –2.9, –2.8, –2.8, –1.8 and –3.6 cm^–1^ for compounds 1–5, respectively. Each type of compound may be distinguished by their characteristic EPR spectrum at 4 K. Fairly good simulations of the spectra at 4 K for the trinuclear compounds 1–3 were obtained with ground state ZFS parameters, D~5/2~ and E~5/2~, of 0.16 cm^–1^ and 0.05 cm^–1^ (1), 0.16 cm^–1^ and 0.043 cm^–1^ (2) and 0.16 cm^–1^ and 0.053 cm^–1^ (3), respectively. For the dinuclear complex 5, the best simulation of the spectrum at 4 K was obtained with ZFS parameters of the ion, D~Mn~ and E~Mn~, of 0.187 cm^–1^ and 0.061 cm^–1^, respectively.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)