Download presentation

Presentation is loading. Please wait.

1
Lecture 30 11/14/05

2
Spectrophotometry

3
Properties of Light h = 6.626 x 10 -34 J-s c = 3.00 x 10 8 m/s

6
Transmittance Absorbance P = Irradiance (Intensity) = energy per second per area of light

7
Beer’s Law A= bc = extinction coefficient or molar absorptivity b = pathlength c = concentration

15
Recap Absorbance Specific wavelengths of light electronic transition UV/Vis: electronic transition Vibrations IR: Vibrations Beer’s Law For Quantitation

16
Beer’s Law Monochromatic light Dilute solutions

17
IC: Internal conversion ISC: Intersystem crossing

18
Luminescence Fluorescence Emission of photon during transition between S 1 S 0 Phosphorescence Emission of photon during transition between T 1 S 0

19
Luminescence More sensitive than absorption Lower energy (higher wavelength) than the energy absorbed

22
IC: Internal conversion ISC: Intersystem crossing

25
I = kP 0 c

26
Excitation spectrum vs. emission spectrum

27
Analysis of a Mixture A = X b[X] + Y b[Y] + Z b[Z] +....

29
Spectra overlap 1.Constant concentration of both analytes 1. Find at different 2.Least squares to find best values of [X] and [Y] 1. A m = X b[X] + Y b[Y] 2. A calc = X b[X] guess + Y b[Y] guess

31
Spectra not-overlapping A’ = ’ X b[X] + ’ Y b[Y] at ’ A’’ = ’’ X b[X] + ’’ Y b[Y] at ’’

32
`

33
Recap Absorbance Specific wavelengths of light electronic transition UV/Vis: electronic transition Vibrations IR: Vibrations Beer’s Law For Quantitation

34
Beer’s Law Monochromatic light Dilute solutions

35
IC: Internal conversion ISC: Intersystem crossing

36
Luminescence Fluorescence Emission of photon during transition between S 1 S 0 Phosphorescence Emission of photon during transition between T 1 S 0

37
Luminescence More sensitive than absorption Lower energy (higher wavelength) than the energy absorbed

40
IC: Internal conversion ISC: Intersystem crossing

43
I = kP 0 c

44
Excitation spectrum vs. emission spectrum

45
Analysis of a Mixture A = X b[X] + Y b[Y] + Z b[Z] +....

47
Spectra overlap 1.Constant concentration of both analytes 1. Find at different 2.Least squares to find best values of [X] and [Y] 1. A m = X b[X] + Y b[Y] 2. A calc = X b[X] guess + Y b[Y] guess

49
Spectra not-overlapping A’ = ’ X b[X] + ’ Y b[Y] at ’ A’’ = ’’ X b[X] + ’’ Y b[Y] at ’’

50
`

51
Recap Absorbance Specific wavelengths of light electronic transition UV/Vis: electronic transition Vibrations IR: Vibrations Beer’s Law For Quantitation

52
Beer’s Law Monochromatic light Dilute solutions

53
IC: Internal conversion ISC: Intersystem crossing

54
Luminescence Fluorescence Emission of photon during transition between S 1 S 0 Phosphorescence Emission of photon during transition between T 1 S 0

55
Luminescence More sensitive than absorption Lower energy (higher wavelength) than the energy absorbed

58
IC: Internal conversion ISC: Intersystem crossing

61
I = kP 0 c

62
Excitation spectrum vs. emission spectrum

63
Analysis of a Mixture A = X b[X] + Y b[Y] + Z b[Z] +....

65
Spectra overlap 1.Constant concentration of both analytes 1. Find at different 2.Least squares to find best values of [X] and [Y] 1. A m = X b[X] + Y b[Y] 2. A calc = X b[X] guess + Y b[Y] guess

67
Spectra not-overlapping A’ = ’ X b[X] + ’ Y b[Y] at ’ A’’ = ’’ X b[X] + ’’ Y b[Y] at ’’

68
`

Similar presentations

© 2019 SlidePlayer.com Inc.

All rights reserved.

To make this website work, we log user data and share it with processors. To use this website, you must agree to our Privacy Policy, including cookie policy.

Ads by Google