Excited states, ligand luminescence

Recently, two cryptands and their lanthanide complexes have been synthesized which include either a bipyridyl (L ) or pyridyl (L ) chromophore 89), These have proved effective at populating the lanthanide excited states. Aqueous luminescence lifetimes of up to 1.12 ms and quantum yields of up to 0.02 (europium) and 0.25 (terbium) are reported. The better luminescence from complexes of ligand is due to the better exclusion of water from the lanthanide center. 

Calculation of the Slater-Condon, spin-orbit coupling and ligand field parameters. The luminescence of CsMgBr3 Eu2+ is crucially dependent on the local coordination geometry of the Eu2+ dopant. Besides, a geometry change occurs in the excited state 4f 5d1 (see Table 2), leading to shifts... 

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