Redes de Coordenação de Íons Lantanídeos e do Bloco Construtor [Cu(bpca)]+: Síntese, Caracterização e Estudo das Transformações Estruturais na Interface Cristal-Solução

Abstract

Three-dimensional molecular networks arouse interest due to their properties and potential applications in several fields of Chemistry and Materials Science. This work presents two studies involving coordination networks: the first them reports coordination networks constituted of lanthanide ions whereas the second study brings a coordination network formed by the building block [Cu(bpca)]+. The first part of the work addresses the synthesis, by the hydrothermal method, and characterization by single crystal X-ray diffraction (SCXRD) and powder X-ray diffraction (PXRD) of ten three-dimensional coordination networks, using the ligand 2,5-pyrazinedicarboxylic acid (H2-2,5-pzdc) and lanthanide ion salts (Ln3+ = Eu3+, Gd3+, Tb3+, and Dy3+). In this work, we present the characterization of structural transformations at the crystalsolution interface using powder X-ray diffraction (PXRD), identifying ten possible crystalline formations. Preliminary refinement data from single-crystal X-ray diffraction (SCXRD) reveal the formation of a group of crystalline structures referred to in this work as Ln-sulfate, Ln-semi-sulfate, and Ln-free-sulfate. The second part presents the synthesis, spectroscopic and thermal characterization as well as structural study of a new heterobimetallic coordination polymer with the molecular formula {[Na(H2O)2][Cu2(bpca)2(CO3)(HCO3)]}n [Hbpca = bis(2-pyridylcarbonyl)amide], which it was obtained through the fixation of atmospheric carbon dioxide by the building block [Cu(bpca)]+ , in a basic water/DMSO (dimethyl sulfoxide) mixture.