Two Sets of Metal-Organic Frameworks along the Lanthanide Series Constructed by 2,3-Dimethylsuccinate: Structures, Topologies, and Strong Emission without Ligand Sensitization

GOMEZ, GERMÁN ERNESTO; BERNINI, M.C; BRUSAU, E.V; NARDA, G.E; MASSAD, W.; LABRADOR, A.

CRYSTAL GROWTH & DESIGN

AMER CHEMICAL SOC

Lugar: Washington; Año: 2013 vol. 13 p. 5249 - 5260

1528-7483

Reactions in aqueous solution under hydrothermal conditionsbetween (±)-2,3-dimethylsuccinic acid and lanthanide chlorides lead to twodifferent isostructural types with chemical formulas [Ln2(C6H8O4)3(H2O)2]Ln(III) = Pr−Eu (except Pm) (Type I, compounds 1−4) and [Ln2(C6H8O4)3]Ln(III) = Tb−Yb (except Tm) (Type II, compounds 5−9). The crystal structurehas been solved for the Pr (1)-, Sm (3)-, and Ho (7)-containing compounds bymeans of single-crystal XRD methods, whereas powder XRD Rietveld refinementwas used for the rest of the MOFs. Compounds 1−4 crystallize in the triclinicspace group P1̅, whereas compounds 5−9 belong to the tetragonal space groupP43212. Type I and II compounds are 3D frameworks consisting of chains of[LnO8(H2O)] or [LnO8] polyhedra, respectively, linked by dimethylsuccinateanions, giving rise to I1O2 connectivity. All the compounds were characterized by X-ray diffraction, variable-temperature Fourier transform infrared spectroscopy, and thermal analysis. An exhaustive topological study was performed in comparison with other related compounds. The photoluminescent (PL) properties for compounds 3, 4, and 5 have been also explored, indicating that a metal-centered luminescent process takes place.