Dihydroxybenzoquinone and chloranilic acid derivatives of rare earth metals

The crystal structures of lanthanide complexes involving the dianions of dihydroxybenzoquinone (H(2)dhbq) or chloranilic acid (H(2)can) are presented. The complexes, Ln(2)dhbq3.24H(2)O (Ln = Y, La, Ce, Gd, Yb and Lu) are 2-D coordination polymers with metal centres linked by dhbq(2-) ligands. Each of these species contain a Ln(2)(H2O)(18) pentagonal dodecahedral cage. Despite the variation in the radii of lanthanide ions this series is isostructural. In contrast, the hydrated structures of Ln(2)can(3) (Ln = Sc, Y, La, Pr, Nd, Gd, Tb, Yb and Lu) show considerable structural variation. The crystal structures of the diamond-like networks Ycan(2)(-) and Thcan(2) are also presented.