Dexter electron transfer

Dexter electron transfer is a quenching mechanism in which an excited electron state transfers from one molecule (the donor) to a second (the acceptor). This requires a wavefunction overlap between the donor and acceptor, so can only occur at short distances; typically of the order 15-20Å. The excited state may be exchanged in a single step, or in two separate charge exchange steps.

The Dexter energy transfer rate, k_ET, is proportional to the expression:

$k_{ET} \varpropto J \mathrm{exp}\left [ \frac{-2r}{L} \right ]$

Where r is the separation of the donor from the acceptor, L is the sum of the van-der Waals radii of the donor and the acceptor and J is the spectral overlap integral:

$J = \int f_{\rm D}(\lambda) \, \epsilon_{\rm A}(\lambda) \, \lambda^4 \, d\lambda$

See also

• Förster resonance energy transfer

References

• http://dpeecs.nctu.edu.tw/.files/OLED_5.pdf
• http://www.iupac.org/goldbook/D01654.pdf