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Title: Accessing the triplet manifold of naphthalene benzimidazole–phenanthroline in rhenium( i ) bichromophores
The steady-state and ultrafast to supra-nanosecond excited state dynamics of fac -[Re(NBI-phen)(CO) 3 (L)](PF 6 ) (NBI-phen = 16H-benzo[4′,5′]isoquinolino[2′,1′:1,2]imidazo[4,5- f ][1,10]phenanthrolin-16-one) as well as their respective models of the general molecular formula [Re(phen)(CO) 3 (L)](PF 6 ) (L = PPh 3 and CH 3 CN) has been investigated using transient absorption and time-gated photoluminescence spectroscopy. The NBI-phen containing molecules exhibited enhanced visible light absorption with respect to their models and a rapid formation (<6 ns) of the triplet ligand-centred (LC) excited state of the organic ligand, NBI-phen. These triplet states exhibit an extended excited state lifetime that enable the energized molecules to readily engage in triplet–triplet annihilation photochemistry.
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Dalton Transactions
Page Range or eLocation-ID:
13086 to 13095
Sponsoring Org:
National Science Foundation
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