Photophysical and Structural Properties of Rare-Earth Phenolate Compounds

Trivalent rare-earth (RE3+) phenolate complexes have been receiving growing attention owing to their remarkable structural, luminescent, and magnetic properties. The RE3+ ions play an important role in the synthetic mechanisms acting as template, leading to a large number of homodinuclear and heterodinuclear coordination compounds presenting macrocyclic and macroacyclic phenolate ligands. The photoluminescent behavior of these kinds of complexes has been attributed to an efficient intramolecular energy transfer from the ligands to the RE3+ ions. The RE phenolate complexes have opened new possibilities for practical applications such as in RE3+ separation, in tunable photonic devices, in fluoroimmunoassays, and as paramagnetic contrast agents in magnetic resonance imaging. Keywords: the chemistry of metal phenolate complexes; structural properties of rare-earth phenolate complexes; RE3+ compounds containing acyclic and cyclic phenolate ligands; rare-earth–hydroxyquinolinate, -hydroxypyridine, -hydroxylpicolinate, -hydroxynicotinate cryptate, and -oxazolylphenol complexes; RE3+ luminescence properties