Synthesis, Characterization and Electrical Conductivity of Mixed-ligand 7, 7, 8, 8-Tetracyanoquinodimethane and 1, 10- Phenanthroline Complexes of Lanthanide Perchlorate

摘要

In order to investigate the coordination properties and conductivity of TCNQ ligand with lanthanide elements and the influence of the constitutive and valence property of metal center and the oxidation state of TCNQ to the conductivity of the complexes, a series of complexes including 7, 7, 8, 8-tetracyanoquinodimethane (TCNQ~0) of lanthanide perchlorates with TCNQ~- and 1, 10-phenanthroline (phen) of the formula [(phen)_3RE(TCNQ)_2~-(TCNQ)_2~-RE(phen)_3] (TCNQ~- )_3 (CIO_4~- ). nH_2O (RE= La, Ce, Eu, Tb, n = 1) are prepared in ethanol. And they have been characterized by elemental analysis, IR spectra, electronic spectra, thermal analysis and molar conductivity. The electrical conductivity of these complexes has been determined by the two probe technique at room temperature. At room temperature, all four compounds behave virtually as semiconductors (σ300k= 10~(-2) - 10~(-3)Som~(-1)). Comparing the conductivity of these complexes with that of transition metals, a conclusion has been supposed: the conductivity of this kind of complexes is influenced by the oxidation state of TCNQ and the valence property of metal center. Our experimental results showed that the conductivity of the complexes including TCNQ~0 is higher than that of the complex only including TCNQ~- and the valence property of metal center might be the most important factor to the conductivity.