CRYSTAL STRUCTURE OF METAL-ORGANICFRAMEWORKS BASED ON TERBIUMAND 1,4-NAPHTHALENEDICARBOXYLIC ACID

The interaction of terbium nitrate pentahydrate and 1,4-naphthalenedicarboxylic acid (H2ndc) in a solvent mixture under solvothermal conditions yields two new metal-organic frameworks: ((CH3)2NH2)2[Tb3(H2O)(HCOO)(ndc)5]∙3DMF (1) and [Tb4(DMF)(NMP)6(ndc)6] (2) (ndc2– is 1,4-naphthalenedicarboxylate, DMF is N,N-dimethylformamide, NMP is N-methyl-2-pyrrolidone). The crystal structures of compounds 1 and 2 are established by the single crystal X-ray diffraction analysis. Compound 1 is a negatively charged 3D framework in which dimethyl ammonium cations act as counterions. The remaining volume available for solvent molecules is filled with DMF. Compound 2 has a dense layered structure. The luminescence spectrum contains one emission band corresponding to π*– π transitions in the ligand.