Crystal structures of two isotypic lanthanide(III) complexes: tri-aqua-[2,6-di-acetyl-pyridine bis-(benzoyl-hydrazone)]methano-llanthanide(III) trichloride methanol disolvates ( Ln III = Tb and Dy).

The title lanthanide complexes, [ Ln (DAPBH2 )(CH3 OH)(H2 O)3 ]Cl3 ·2CH3 OH [ Ln III = Tb and Dy; DAPBH2 = 2,6-di-acetyl-pyridine bis-(benzoyl-hydrazone), C23 H21 N5 O2 ], are isotypic. The central lanthanide ions are nine-coordinate, being ligated by three N and two O atoms from the penta-dentate DAPBH2 ligand, and four O atoms from the coordinated methanol mol-ecule and three coordinated water mol-ecules. The coordination geometry of the lanthanide ion is a distorted capped square anti-prism. In the crystals, the various components are linked by O-H⋯Cl, N-H⋯Cl and O-H⋯O hydrogen bonds, forming three-dimensional supra-molecular frameworks. Within the frameworks, there are C-H⋯Cl and C-H⋯O hydrogen bonds and offset π-π inter-actions (inter-centroid distance ca 3.81 Å).