Guy Cox wrote:
>
> >
> >It also does what M Serrano calls upconvert - emit at lower wavelength than
> >excite and is not a 2 photon event
> >
> >Ex 633  Em 580
> >
>
>
> And it IS really a two-photon event - it just doesn't behave like one.
> (It shows 1-photon kinetics and doesn't require huge light fluxes but
> two photons are absorbed to generate one photon of fluorescence.)
>
Is it a 2-photon effect, or is it a Raman effect (photon+vibration-mode)
if it is
a Raman effect, it will dissappear at low temperatures since it would be
anti-stokes
(that is, it requires an existing vibration mode to provide the
additional energy).

--aryeh
--
Aryeh Weiss                          | email: [log in to unmask]
Department of Electronics            | URL:
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