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  Rotational Raman Spectroscopy
Temperature page 1 of 2
   
Practical Navigator
Introduction
The Raman Effect
Experimental Techniques
1. Rotational Raman Spectroscopy
Interpreting the Spectrum
Effect of Bond Length
Centrifugal Distortion
Intensities of Spectral Lines
Nuclear Spin Statistics
2. Real Diatomic Molecules
Temperature
Spectrum of Nitrogen
Isotopic Substitution
Nuclear Spin Statistics
Predict the Spectrum of Oxygen
  The temperature of the sample greatly affects any kind of spectrum. Changing average energy of the gas must change the . With knowledge of the line intensity only; the rotational constant of the molecule can be calculated.

Launch Applet 3 to bring up the simulation for this section.

Q5.1 Why are more spectral lines visible at higher temperatures?
Q5.2 How would you expect the intensity of the first Anti-Stokes line to vary with temperature?
Q5.3 How does the intensity of the first Stokes line vary with temperature? Why is this the case?
Q5.4 From the applet, note the value of J at which line intensity is a maximum for ten different temperatures.
Q5.5 Why are the maximum intensities at higher temperatures more intense than at lower temperatures?
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