L1 /
10
CH3041
FLUORESCENCE
• Fluorescence
measures an electronic transition between electronic states with
the same spin quantum nos.
S1 ® S0 + hn
singlet excited state ® singlet ground state
singlet excited state ® singlet ground state
• A light beam is shone on the sample and
the emission is measured at 90o.
the emission is measured at 90o.
Monochromator
Detector
Light
Source
Source
UV
emission signal
Sample
(1 wavelength)
(photomultiplier
or diode array)
Monochromator
(1 wavelength)
• I = k Po [i] I emission intensity
Po incident power
• Used in SO2 analysis IDL
2ppb,
PAH .
