Combined ultrafast spectroscopic and TDDFT theoretical studies on dual fluorescence emissions promoted by ligand-to-metal charge transfer (LMCT) excited states of tungsten -containing organometallic complexes

摘要

In this work, we first designed and synthesized two tungsten-containing organometallic complexes MeNOON and MeNOOO with novel dual fluorescence emissions. Moreover, the combined femtosecond ultrafast spectroscopy and time-dependent density functional theory (TDDFT) method has been performed to investigate the excited-state dynamics of MeNOON and MeNOOO complexes. It is distinctly demonstrated that dual fluorescence emissions of tungsten-containing organometallic complexes are originated from the localized-on-ligand (LL) and ligand-to-metal charge transfer (LMCT) excited states, respectively. Furthermore, the ultrafast LMCT process has been measured by the femtosecond spectroscopy.