Aplicação do cátion coordenante N-metil-4,4'-bipiridínio na síntese de materiais moleculares em combinação com os blocos construtores [Ni(dmit)2]²- (dmit = 1,3-ditiol-2-tiona-4,5-ditiolato) e [Cu(opba)2]²- (opba = orto-fenilenobisoxamato)

Abstract

In the work described within this dissertation, two new coordination compounds were synthesized and characterized, (mb)2[Ni(dmit)2] ((dmit)2- = 1,3-dithiole-2-thione-4,5- dithiolate, (mb)+= N-methyl-4,4’-bipyridinium) and [Cu(mb)2(opba)2] (opba = orthophenylene-bis(oxamate)), which were applied in supramolecular fabrication strategies to create nanomaterials. The amount of metals in the coordination compounds were determined by atomic absorption spectroscopy (AAS) and the following chemical elements were determined by elemental analysis of carbon, hydrogen, nitrogen and sulphur (CHNS). The characterization of the coordination compounds was completed using infrared spectroscopy (IV), ultraviolet-visible absorption spectroscopy (UV-vis), Raman spectroscopy and thermogravimetric analysis (TG, DTG and DTA). Using (mb)2[Ni(dmit)2] as a precursor a hybrid material in which the [Ni(dmit)2]2- building block was deposited over a nanometric substrate of polymeric carbon nitride (NCP), the hybrid nanocomposite material obtained was labeled (mb)-Ni(dmit)-NCP. This material was synthesized through a deposition reaction the building block over the NCP surface not yet reported in the scientific literature. During the characterization of the nanocomposite, it was demonstrated that the deposition process is mediated by the presence of the coordination cation (mb)+, doesn’t involve the photo-oxidation or photoreduction of the building block, requires the doping of the NCP substrate with O or S and that the materials created are stable when suspended in organic solvents by sonication. The nanocomposite (mb)-Ni(dmit)-NCP was characterized by Ni AAS, CHNS, TG, DTG, DTA, IV and powder-based x-ray diffraction spectroscopy (XRD). Using [Cu(mb)2(opba)2] as a precursor, a new trinuclear nanomagnet, labeled mbMnCu2, was obtained through the light-driven supramolecular reorganization of a known coordination polymer. This nanomagnet was characterized by single crystal XRD. It was shown qualitatively that the process that produces this nanomagnet requires light irradiation and the presence of the coordinating cation (mb)+. Using the same coordination compound, now in a direct route, a new chain of trinuclear nanomagnets labeled 1D-mbMnCu2, which was characterized by IV, Raman, powder XRD and single crystal XRD.