Sm（Ⅲ）-Bi（Ⅲ） Heterometallic Complexes with Aminopolycarboxylate Ligand： Structure, Thermal Stability and Spectral Property

摘要

Samnium（Ⅲ）-bismuth（Ⅲ） heterobimetallic complexes, SmBi（edta）（NO3）2·7H2O （1） and SmBi（dtpa）（NO3）·3.5H2O（2） （edta=ethylenediaminetetraacetate, dtpa=diethylenetriaminepentaacetate）, were synthesized and characterized by means of X-ray single crystal diffraction, X-ray powder diffraction, elemental analysis, ICP, FT-IR spectra and thermal analysis. The structure analysis revealed that 1 is in crystalline and 2 is in non-crystal state. Complex 1 crystallizes in monoclinic, space group P2（1） with a= 1.2622（2） nm, b=0.81157（15） nm, c=2.3634（5） nm, β= 105.340（2）°, V=2.3347（8） nm3, Z=4, Dc=2.563 gocm^-3,μ=10.125 mm-1. Bridging edta4 anions between Bi（Ⅲ） atoms and Sm（Ⅲ） atoms result into infinite 3D network structure. Thermal decomposition of the two complexes proceeds in similar stages, i.e., dehydration, pyrolysis of ligand, and decomposition of salt, and the final residue is oxide. In addition, the spectral properties have been studied through FL spectra and UV-Vis DRS. The two complexes exhibit one broad band Bi 6s6p-6s2 emission under UV excitation and the characteristic Sm3＋ ion 4G5/2→6Hj/2 （J= 5, 7, 9, 11） transitions under visible light excitation, respectively.