Long-lived platinum(II) diimine complexes with broadband excited-state absorption: efficient nonlinear absorbing materials.

Platinum(II) diimine complexes with naphthalimide substituted fluorenylacetylide ligands are synthesized and characterized. The complexes exhibit long-lived (3)ILCT or (3)ILCT/(3)MLCT/(3)LLCT excited states (τ = ~20-30 μs) and broadband triplet transient absorption in the visible-NIR region. Nonlinear transmission experiments at 532 nm demonstrate that these complexes are efficient nonlinear absorbing materials.