A tri-layer structure consisting of novel heptacobaltate clusters and single cobalt centers bridged by 5-tert-butyl isophthalate.

A 2D tri-layer compound {[Co(8)(tbip)(6)(H(2)O)(9)(OH)(4)]·12(H(2)O)}(n) (1) (H(2)tbip = 5-tert-butyl isophthalic acid) consisting of novel heptacobaltate clusters and single cobalt centers bridged by tbip(2-) ligands has been hydrothermally synthesized. The complex represents a rare example of a homometallic coordination polymer built up from both heptanuclear metal clusters and single metal centers simultaneously. The magnetic investigation reveals that the complex exhibits the overall predominance of antiferromagnetic coupling between magnetic centers.

1,4-Bis(1H-benzimidazol-2-yl)benzene methanol monosolvate.

The asymmetric unit of the title compound, C(20)H(14)N(4)·CH(4)O, contains two independent half-mol-ecules, each located on an inversion centre, and a methanol solvent mol-ecule. The benzimidazolyl groups form different dihedral angles [24.0 (1) and 11.6 (1)°] with the plane of the central benzene ring in the two mol-ecules. In the crystal, a two-dimensional network is formed through N-H⋯ N, N-H⋯O and O-H⋯N hydrogen-bonding inter-actions between the benzimidazole units and methanol solvent mol-ecules. π-π stacking inter-actions also occur between the benzimidazole rings of adjacent mol-ecules, with centroid-centroid distances of 3.720 (14) Šand inter-planar distances of 3.53 (1) Š.