Lanthanide complexes of some high energetic compounds (III), crystal structures and thermal properties of 2,6-dinitrophenol (2,6-DNP) complexes

Abstract

The Ln(III) complexes with 2,6-dinitrophenol (2,6-DNP) ligand, [La 2(2,6-DNP) 6(H 2O) 4]·4H 2O, 1, and [Tb(2,6-DNP) 3(H 2O) 3], 2, have been synthesized and their crystal structures have been analyzed by X-ray diffraction methods. Complex 1 and 2, both crystallize in the triclinic space group P 1 ¯ . In complex 1, 2,6-DNP acts as the bidentate. The structural feature is the presence of the bridged ligands and the terminal ligands in the bimetallic structure. In addition, there are four uncoordinated water molecules in the crystal lattice. The 10 coordinated La(III) ion forms a bicapped square antiprism. In complex 2, three 2,6-DNP ligands coordinate directly to the metal ion in the bidentate fashion. The nine coordinated Tb(III) ion forms slightly distorted tricapped trigonal prism. There are no water molecules in the crystal lattice. Based on the results of TG-DTG and DSC thermal analysis, it was analyzed that the lanthanide 2,6-DNP complexes are thermally decomposed in three distinctive stages, the dehydration, the 2,6-DNP decomposition, and the formation of the metal oxide.