The Ce-III, Pr-III, Nd-III, Gd-III and Yb-III complexes of the heptadentate
ligand 2,2',2''-tris(salicylideneimino) triethylamine, H(3)trensal (in its
trianionic form), have been synthesized and characterized structurally by
X-ray crystallography. These five [Ln(trensal)] structures complete a rare
isomorphous and isostructural series of lanthanoid complexes in the trigona
l P (3) over bar c1 space group with a approximate to 13.1 and c approximat
e to 16.5 Angstrom.