10.1021/jp312740b.s001 Hung-Chu Chiang Hung-Chu Chiang Nobuhiro Ohta Nobuhiro Ohta External Electric Field Effect on Fluorescence Spectra of Pyrene in Solution American Chemical Society 2016 External Electric Field Effect excimer fluorescence application nonradiative decay process monomer fluorescence pyrene 2016-02-19 12:04:07 Journal contribution https://acs.figshare.com/articles/journal_contribution/External_Electric_Field_Effect_on_Fluorescence_Spectra_of_Pyrene_in_Solution/2424577 Electrophotoluminescence (E-PL) spectra, i.e., plots of the electric-field-induced change in photoluminescence intensity as a function of wavenumber, have been measured for pyrene solution. At high concentrations of pyrene where excimer fluorescence is observed along with the monomer fluorescence emitted from the locally excited state, both excimer fluorescence and monomer fluorescence are enhanced by application of electric fields. The results show that the nonradiative decay process at the excimer emitting state is decelerated by application of electric fields. It is also found that molecular polarizability of pyrene excimer is larger than that of pyrene monomer in the ground state by ∼270 ± 90 Å<sup>3</sup>, based on the analysis of the Stark shift of the excimer fluorescence.