Abstract
The title compound, [Mn6(C7H4NO3)5(CHO2)2(C3H4N2)5(CH3OH)]·3.36CH3OH·0.65H2O, or Mn(II)(O2CH)2[15-MCMn(III)N(shi)-5](Im)5(MeOH)·3.36MeOH·0.65H2O (where MC is metallacrown, shi(3-) is salicyl-hydroximate, Im is imidazole and MeOH is methanol), contains five Mn(III) ions as members of the metallacrown ring and an Mn(II) atom bound in the central cavity. The central Mn(II) atom is seven-coordinate with a geometry best described as between face-capped trigonal-prismatic and face-capped octa-hedral. Three Mn(III) ions of the metallacrown ring are six-coordinate with distorted octa-hedral geometries. Of these six-coordinate Mn(III) ions, two have mirror-plane configurations, while the other has a Δ absolute stereoconfiguration. The remaining two Mn(III) ions have a coordination number of five with a distorted square-pyramidal geometry. The five imidazole ligands are bound to five different Mn(III) ions. Disorder is observed for one of the coordinating imidazole ligands, as the imidazole ligand is disordered over two alternative mutually exclusive positions in a ratio of 0.672 (9) to 0.328 (9). The inter-stitial voids between the main mol-ecules that constitute the structure are mostly filled with methanol mol-ecules that form hydrogen-bonded chains. Some of the sites of the non-coordinated methanol mol-ecules are not fully occupied, with the remainder of the volume either empty or taken up by ill-defined close to amorphous content. One site was refined as being taken up by either two or one methanol mol-ecules, with an occupancy ratio of 0.628 (5) to 0.343 (5). This disorder might thus be correlated with the disorder of the imidazole ring (an N-H⋯O hydrogen bond between the major moieties of the imidazole and the methanol mol-ecules is observed). On the other side of the disordered imidazole ring the chain of partially occupied methanol mol-ecules originates that extends via O-H⋯O hydrogen bonds to the metal-coordinated methanol mol-ecule. The three partially occupied methanol mol-ecules were refined to be disordered with two water mol-ecules to take two residual electron density peaks into account (the exact nature of these weak residual electron density peaks cannot be deduced from the X-ray diffraction data alone, the assignment as water is tentative). The occupancy rate for the methanol mol-ecules refined to 0.480 (7). The occupancy rate of the two water mol-ecules refined to 0.34 (1) and 0.31 (2) for each site.