UPSC Combined Geo-Scientist, Mains · 2016 · Mains Paper II
Q12(b)(i). Raman-scattering lines
Question
What are Rayleigh, Stokes and anti-Stokes lines? Are Stokes and anti-Stokes intensities different? Explain.
Answer in brief
Rayleigh scattering is elastic; Stokes scattering leaves the molecule more energetic, whereas anti-Stokes scattering removes pre-existing molecular excitation.
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CoversRaman-scattering linesRaman spectroscopy
All parts of Question 12
- 12(a)(i) Energy absorbed by HI3 marks
- 12(a)(ii) Counting normal modes4 marks
- 12(a)(iii) Microwave activity3 marks
- 12(b)(i) Raman-scattering lines5 marks
- 12(b)(ii) Carbon dioxide normal modes5 marks