Synthesis, crystal structure and thermogravimetric analysis of maleato bridged phenanthroline complexes

The polynuclear complexes poly-[(mu-maleato-O : O')(1,10-phenanthroline-N : N')-diaquacobalt] dihydrate, 1, and the isostructural manganese compound, 2, have been prepared and characterized by elemental analysis, IR spectra and thermogravimetric studies. The crystal structure of 1 is a one-dimensional infinite chain. Each Co atom is six-coordinated with two water molecules arranged cis. Co-O(water) distances are 2.0686(13) and 2.1531(13) Angstrom and the Co-O(maleato) distances are 2.0954(13) and 2.1197(12) Angstrom. The bite angle of phenanthroline to Co is 77.20(6)degrees with Co-N distances of 2.155(2) and 2.1531(14) Angstrom. Complex 2 has an identical structure to complex 1. IR spectra indicate the presence of water molecules. Absorption peaks at 1546 and 1432 cm(-1) for 1 and at 1540 and 1425 cm(-1) for 2 are assigned to carbonyl asymmetric and symmetric vibrations, respectively. The two coordinated water molecules together with the two lattice water molecules for 1 are confirmed by thermogravimetric analysis.