 听 |
To date, the piling up of successive photons of low energies (near infrared; NIR) using a single lanthanide center and linear optics to ultimately produce upconverted visible emission was restricted to low鈥恜honon solid materials and nanoparticles. Now we show that the tight helical wrapping of three terdentate N鈥恉onor ligands around a single nine鈥恈oordinate trivalent erbium cation provides favorable conditions for a mononuclear molecular complex to exhibit unprecedented related upconverted emission. Low power NIR laser excitations into the metal鈥恈entered transitions Er(4I11/2鈫�4I15/2) at 801鈥卬m or Er(4I13/2鈫�4I15/2) at 966鈥卬m result in upconverted blue鈥揼reen emissions, where two or three photons respectively are successively absorbed by a molecular lanthanide complex possessing high鈥恊nergy vibrations.
DOI:
Archive ouverte / Open archive: