Structural variations in terbium(III) complexes with 1,3-adamantanedicarboxylate and diverse co-ligands

Cucurbit[n]uril-Based Supramolecular Frameworks Assembled through Outer-Surface Interactions

Porous materials, especially metal-organic frameworks, covalent organic frameworks, and supramolecular organic frameworks, are widely used in heterogeneous catalysis, adsorption, and ion exchange. Cucurbit[n]urils (Q[n]s) suitable building units for porous materials because they possess cavities with neutral electrostatic potential, portal carbonyls with negative electrostatic potential, and outer surfaces with positive electrostatic potential, which may result in the formation of Q[n]-based supramolecular frameworks (QSFs) assembled through the interaction of guests within Q[n]s, the coordination of Q[n]s with metal ions, and outer-surface interaction of Q[n]s (OSIQ). This review summarizes the various QSFs assembled via OSIQs. The QSFs can be classified as being assembled by 1) self-induced OSIQ, 2) anion-induced OSIQ, and 3) aromatic-induced OSIQ. The design and construction of QSFs with novel structures and specific functional properties may establish a new research direction in Q[n] chemistry.

Assemblies of cucurbit[6]uril-based coordination complexes with disulfonate ligands: from discrete complexes to one- and two-dimensional polymers

Nine assemblies of Q[6]-based coordination complexes incorporating disulfonate ligands were obtained and two of them were found to have the ability to sense Fe³⁺via a fluorescence quenching effect.

Electronic structure and spectral properties of terbium(III) nitrate complex with hexamethylphosphoramide

Spectral properties of terbium(III) nitrate complex with hexamethylphosphoramide have been studied by quantum-chemical methods within the density functional theory and methods of luminescent and X-ray photoelectron spectroscopy. Analysis of the luminescence excitation spectrum of the complex has indicated the absence of intramolecular transfer of electronic excitation energy from the ligand levels to the resonance levels of the rare earth central ion, so luminescence of the complex is associated with the electronic f-f-transitions of Tb³⁺ ion (transitions ⁵D₄→⁷F_J, J=3-6). According to quantum-chemical modeling of the excited singlet and triplet levels of the complex, the excitation energy transfer from the ligands onto the central ion does not occur because of the significant difference of energies of their excited states.