New Properties and Characteristics of Mixed LigandCoordination Polymers Derived from TransitionMetal Ions, 1,2,4,5-Benzenetetracarboxylate andAromatic Diamines

摘要

Coordination polymers derived from 1,2,4,5-benzenetetracarboxylate (H2btec~(2-) or btec~(4-) ), Fe(II), Mn(II), Co(II), Ni(II), Cu(II), Cd(II) or UO_(2)(II) metal ions, 1,10-phenanthroline(1,10-phen) or 2,2'-bipyridine(2,2'-bipy) were prepared. The polymers were characterized by elemental analysis, IR and electronic spectra, electrical conductance, magnetic susceptibility measurements and thermal behavior. The electronic spectra, magnetic susceptibility measurements and X-ray structure determination revealed octahedral and tetrahedral geometries around the metal ions. Kinetic and thermodynamic parameters of the thermal decomposition were computed from the thermal data using the Coats-Redfern equation. From the X-ray powder diffraction the particle sizes (6.4-25.4 nm) of the coordination polymers could be calculated using the Scherrer`s equation.