The Perrin-Jablonski Diagram
The life history of an excited state electron in a luminescent probe
Key points:
üExcitation spectra are mirror images of the emission spectra
üEmission has lower energy compared to absorption
üTriplet emission is lower in energy compared to singlet emission
üMost emission/quenching/FRET/chemical reactions occur from the lowest vibrational level of [S]1
 
Internal
conversion 10-12s
Fluorescence
10-9s
Phosphorescence
           10-3s
Radiationless
Decay <10-9s
G
S2
S1
T1
kT thermal equilibration
Inter-system
Crossing 10-10s
Absorption
10-15s
GM
Perrin-Jablonski Diagram