Hydrothermal treatment of a mixture of H3imdc (4,5-imidazoledicarboxylic acid), Na2SO4, Dy(NO3)3·6H2O
and NaOH generated a novel inorganic–organic hybrid framework, {[Dy2(SO4)(Himdc)2(H2O)5]·H2O}n (1).
Its crystal structure contains alternately arranged 1D left- and right-handed helical {Dy(Himdc)}n chains,
each helical chain is composed of alternately arranged Dy(1) and Dy(2) ions connected by Himdc2– with
bis(bidentate) linking mode. Every three helical chains are bridged by inorganic SO4 2− anions, which link
Dy3+ ions in a tris(monodentate) mode to form a 3D framework. Compound 1 displays intense yellow
photoluminescence corresponding to the characteristic 4F9/2 → 6HJ transitions of the Dy3+ ion.