Solvothermal Syntheses and Characterization of Three Lanthanide Thioantimonates(V) with Mixed Ethylene Polyamines

摘要

Three new lanthanide thioantimonates(V) [Ln(en)(teta)(SbS_4)] {Ln=Sm (1), Eu (2), Gd (3); en=ethylenediamine; teta=triethylenetetramine} have been solvothermally synthesized and structurally characterized. Compounds 1 - 3 are isostructural. The [SbS_4]~(3-) anion acting as bichelating ligand is bound to the [Ln(en)(teta)]~(3+) ion, resulting in a neutral complex [Ln(en)(teta)(SbS_4)]. The central Ln~(3+) ion lies within an eight-coordinate environment forming a distorted bicapped trigonal prism LnN_6S_2. Although a few lanthanide thioantimonates have been reported to date, they only contain one type of ethylene polyamine. Compounds 1 - 3 are rare examples of lanthanide thioantimonates with mixed ethylene polyamine ligands. The absorption edges of 1.75 eV for 1 and 2.27 eV for 3 have been derived from optical absorption spectra.