Abstract
Three azido‐bridged Mn^II^ complexes of formulas [Mn~2~(N~3~)~4~(ttp)~2~] (1), [Mn~2~(N~3~)~4~(ttp‐N~3~)~2~] (2) and [Mn~2~(N~3~)~4~(ttp‐N~3~)~2~]~3~[Mn^III^(ttp‐N~3~)(N~3~)~3~]~2~ (3), where ttp and ttp‐N~3~ represent 4′‐p‐tolyl‐2,2′:6′,2″‐terpyridine and 4′‐p‐azidomethylphenyl‐2,2′:6′,2″‐terpyridine, were synthesized and characterized by single‐crystal X‐ray diffraction analysis and magnetic studies. The Mn ions in complexes 1 and 2 are coordinated by three N atoms of the ttp or ttp‐N~3~ ligands, and they are connected by double end‐on (EO) azide ligands; this forms a dinuclear Mn^II^ system with Mn–N–Mn bridging angles of 103.5 and 103.1°. The Br atoms of the –CH~2~Br ligands were replaced by azido groups during the formation of complexes 2 and 3. The structure of complex 3 comprises two structurally similar Mn^II^ dimers with double end‐on bridging azide groups and one mononuclear Mn^III^ structure. The bridging Mn–N–Mn angles in 3 are 104.2, 105.1, and 106.73°. Magnetic studies indicate the presence of intramolecular ferromagnetic superexchange. The strength of ferromagnetic coupling within the Mn~2~ cores in 1–3 is dependent on the Mn–N–Mn bridging angles. The magnetic coupling constants for intermolecular exchange are 2.46(4), 2.25(2), and 1.92(4) cm^–1^ for 1, 2, and 3, respectively, on the basis ofHamiltonian Ĥ = –2__J__Ŝ~1~Ŝ~2~.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)