Poly[aqua(μ3-benzene-1,2-dicarboxylato)bis(μ3-hydroxido)bis(μ2-isonicotinato)dierbium(III) monohydrate] and the thulium analogue.

The two isomorphous lanthanide coordination polymers, {[Ln2(C6H4NO2)2(C8H4O4)(OH)2(H2O)]·H2O} n (Ln = Er and Tm), contain two crystallographically independent Ln ions which are both eight-coordinated by O atoms, but with quite different coordination environments. In both crystal structures, adjacent Ln atoms are bridged by μ3-OH groups and carboxylate groups of isonicotinate and benzene-1,2-dicarboxylate ligands, forming infinite chains in which the Er...Er and Tm...Tm distances are in the ranges 3.622 (3)–3.894 (4) and 3.599 (7)–3.873 (1) Å, respectively. Adjacent chains are further connected through hydrogen bonds and π–π interactions into a three-dimensional supramolecular framework. [ABSTRACT FROM AUTHOR]