1 research outputs found
Polyphenylcyclopentadienyl Ligands as an Effective Light-Harvesting π‑Bonded Antenna for Lanthanide +3 Ions
A new approach to
design “antenna-ligands” to enhance the photoluminescence
of lanthanide coordination compounds has been developed based on a
Ď€-type ligandî—¸the polyphenyl-substituted cyclopentadienyl.
The complexes of di-, tri-, and tetraphenyl cyclopentadienyl ligands
with Tb and Gd have been synthesized and all the possible structural
types from mononuclear to di- and tetranuclear complexes, as well
as a coordination polymer were obtained. All types of the complexes
have been studied by single-crystal X-ray diffraction and optical
spectroscopy. All terbium complexes are luminescent at ambient temperature
and two of them have relatively high quantum yields (50 and 60%).
Analysis of energy transfer process has been performed and supported
by quantum chemical calculations. The role of a low-lying intraligand
charge transfer state formed by extra coordination with K<sup>+</sup> in the Tb<sup>3+</sup> ion luminescence sensitization is discussed.
New aspects for design of lanthanide complexes containing π-type
ligands with desired luminescence properties have been proposed