Phenolate- and Acetate (Both μ2-1,1 and μ2-1,3 Modes)-Bridged Linear CoII3 and CoII2MnII Trimers: Magnetostructural Studies

A full report on the synthesis, crystal structure, spectroscopic characterization, and magnetic properties of two new trinuclear complexes (one homo- and another heterotrinuclear) [(L)(2)Co-3(II)(OAc)(4)(MeOH)(2)]center dot 6MeOH (1) and [(L)(2)(Co2MnII)-Mn-II(OAc)(4)(MeOH)(2)]center dot 6MeOH (2) [HL = N-methyl-N-2-hydroxybenzyl-2-aminoethyl-2-pyridine] is presented. The properties of 1 and 2 are compared to that of three previously communicated complexes [(L)(2)Ni-3(II)(OAc)(4)(MeOH)(2)]center dot 6MeOH (3), [(L)(2)(Ni2MnII)-Mn-II(OAc)(4)(H2O)(2)] (4), and [(L)(2)(Ni2CoII)-Co-II(OAc)(4)(MeOH)(2)]center dot 6MeOH (5) (Inorg. Chem. 2007, 46, 5128-5130). All are centrosymmetric trimers with the central metal ion situated on an inversion center. Adjacent metal ions are triply bridged by a mu(2)-phenolate and two acetate (one in mu(2)-1,1 mode and another in mu(2)-1,3 mode) groups. Magnetic investigations reveal that the complexes are ferromagnetically coupled (J in cm(-1)): +1.20 (1) and +0.71 (2). The reported J values are +1.10 (3), -0.30 (4), and +1.06 (5). It reveals that total spins are as follows: S = 9/2 (1), 11/2 (2), 3 (3), 1/2 (4), 7/2 (5). The role of M-O(mu(2)-phenoxide)-M', M-O(mu(2)-1,1-acetate)-M', and M-O(mu(2)-1,3-acetate)-M' (M = M' = Co-II, Ni-II; M = Co-II, M' = Mn-II; M = Ni-II, M' = Mn-II, COII) bond angles, on the observed magnetic behavior has been noted