The excited singlet state absorption spectrum of 1,4-diphenylnaphthalene

Modelling excited state absorption (ESA) measurements including the photophysical hole burning effect with rate equations

“…With this approximation the system of differential equations for the population densities (7,8) becomes simply algebraic…”

“…The matrix P contains all the transitions elements of equation (8) and the vector O represents the inhomogeneity N O of equation (9) after substitution of one equation of (8) with (9). The values at the time t.+ 1 follow from the values at the previous time t, using the step width At with the difference approximation by t.+l = t. + At = (n + 1)At + /start, …”

“…Although the first observation of excited state absorption in the triplet [1] and singlet [2,3] system were done more than 45 and 20 years ago and numerous publications described ESA spectra qualitatively (as optical density), only few ESA cross sections were determined quantitatively (see [4][5][6][7][8][9][10][11][12][13][14][15][16]). The main problem of the quantitative evaluation of the high intensity measurements is the determination of the population densities of all occupied states for the performed experiment.…”