Transmittance
Absorbance TlogP
PlogA
P
PT
0
0
P = Irradiance (Intensity) = energy per second per area of light
Recap
Absorbance Specific wavelengths of light UV/Vis: electronic transitionelectronic transition IR: VibrationsVibrations
Beer’s Law For Quantitation
Luminescence
Fluorescence Emission of photon during transition between
S1 S0
Phosphorescence Emission of photon during transition between
T1 S0
Luminescence
More sensitive than absorption Lower energy (higher wavelength) than the
energy absorbed
Spectra overlap
1. Constant concentration of both analytes1. Find at different
b[Y]
A ε
b[X]
Aε Y
YX
X
2. Least squares to find best values of [X] and [Y]1. Am = Xb[X] + Yb[Y]
2. Acalc = Xb[X]guess + Yb[Y]guess
Recap
Absorbance Specific wavelengths of light UV/Vis: electronic transitionelectronic transition IR: VibrationsVibrations
Beer’s Law For Quantitation
Luminescence
Fluorescence Emission of photon during transition between
S1 S0
Phosphorescence Emission of photon during transition between
T1 S0
Luminescence
More sensitive than absorption Lower energy (higher wavelength) than the
energy absorbed
Spectra overlap
1. Constant concentration of both analytes1. Find at different
b[Y]
A ε
b[X]
Aε Y
YX
X
2. Least squares to find best values of [X] and [Y]1. Am = Xb[X] + Yb[Y]
2. Acalc = Xb[X]guess + Yb[Y]guess
Recap
Absorbance Specific wavelengths of light UV/Vis: electronic transitionelectronic transition IR: VibrationsVibrations
Beer’s Law For Quantitation
Luminescence
Fluorescence Emission of photon during transition between
S1 S0
Phosphorescence Emission of photon during transition between
T1 S0
Luminescence
More sensitive than absorption Lower energy (higher wavelength) than the
energy absorbed
Spectra overlap
1. Constant concentration of both analytes1. Find at different
b[Y]
A ε
b[X]
Aε Y
YX
X
2. Least squares to find best values of [X] and [Y]1. Am = Xb[X] + Yb[Y]
2. Acalc = Xb[X]guess + Yb[Y]guess