When we fit (Lorentzian or Gaussian) the Raman peaks, we will get the following three parameters.
1. height,
2. Area under the peak,
3. width.
Out of 1 (height of the peak) and 2 (area under the peak), what is Raman intensity? And Why?
Also, please explain me, what is the difference between the intensity and integrated intensity?
I kindly request you to clear this doubt.
Thanks.
Dear Sir. Concerning your issue about the Raman intensity. The measurements of the Raman intensity are used mainly to determine quantitatively the amount, distribution and degree of crystallisation of different phases in a material, i.e. the Raman mapping. I think the following below links may help you in your analysis:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4019428/
https://www.sciencedirect.com/science/article/pii/S0925346709000871
http://www.ccmr.cornell.edu/wp-content/uploads/sites/2/2016/08/Wire4_Training_Modules_Compilation-Part-4.pdf
Thanks
Intensity (I) could be either peak height intensity, i.e. the intensity above background, or integrated intensity, i.e. the area under the peak. So, the intensity could refer to both. For some systems it is better to work in peak height intensity, while for others in area. The integrated area is directly proportional to the volume amount of material that vibrates in that mode, while the peak height is proportional to the number of molecules that are vibrating at the mean value for that specific mode.
Thank you Isam Eldin Hussein Elgailani and Catalin Croitoru for your information.
From my point of view Catalin Croitoru approaching the question in the correct direction (to the point). However, i am not fully understand the answers.
As per my understanding, you are saying that the height of the peak and area under the peak are essentially giving the more or less similar information. But, the physical origin of the both (height of the peak and area under the peak) of them looks slightly (specifically) different. How can we understand and distinguish, if it is same?
I will try to explain my question with the illustrative example. I am working on the system AB2 stoichiometric crystals. It is a semiconductor. Now, I am doping the element C at the B site. Now, I have stoichiometric crystals like AB2-xCx (X=0.01, 0.3, 0.05, 0.1, 0.2). For 5% doping, the system is going to a metal (confirmed by resistivity study). In this case (5 %, metal), Raman spectrum shows very less height of the peak [compared to semiconductor case (1%, 2%, 3% doping)]. In fact, this was expected due to the penetration depth changes. From electrodynamics, metal will have lesser penetration depth than semiconductor or insulator. Hence height of the Raman peak will expect to decrease compared to semiconductor or insulator at constant configuration (same wavelength, same power, same time of accumulations etc.).
In this controlled experiment, I would like to plot the following,
1. percentage of doping vs. Height of the particular Raman peak
2. and percentage of doping vs. Area of the particular Raman peak
Out of these, which one is more appropriate to tell as metal as a function of doping?
I kindly request you to clarify this doubt. It will really help me a lot.
Thanks.
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