title: Curcuminoid ligands for sensitization of near-infrared lanthanide emission.
abstract: Fluorescent lanthanide complexes were synthesized using a non-phenolic analog of curcumin as the principal chromophoric chelating ligand. Sensitized, near-infrared fluorescence is observed in these complexes as a result of photo-excitation of the chromophoric ligands, population of the molecular triplet state, and transfer of energy to the emitting lanthanide ion. For the purpose of intra-molecular energy transfer, the triplet states of curcuminoid ligands are more favorably matched with the excited electronic states of neodymium and ytterbium ions than those associated with less conjugated beta-diketonate ligands. Sensitization of fluorescence through an internal redox reaction, thought to occur in other ytterbium complexes, is predicted to be less probable under the present circumstances.
authors.affiliation: Chemistry and Materials Division, Naval Air Warfare Center, 1900 N. Knox Road Stop 6303, China Lake, California 93555-6106, USA. michael.seltzer@navy.mil
authors.forename: M D
authors.initials: MD
authors.lastname: Seltzer
authors.forename: S
authors.initials: S
authors.lastname: Fallis
authors.forename: R A
authors.initials: RA
authors.lastname: Hollins
authors.forename: N
authors.initials: N
authors.lastname: Prokopuk
authors.forename: R N
authors.initials: RN
authors.lastname: Bui