Introduction to spectroscopy

Introduction to spectroscopy: part 1

The interaction between matter and radiation can be analyzed through spectroscopy.

Radiation: basically radiation is energy transferred by electromagnetic waves. It includes x rays, gamma rays, visible light... etc.


Properties of electromagnetic waves:






v All electromagnetic waves travel at the same speed (C)
v Wave length: ( λ) the length of one complete cycle
v Amplitude: (A) Half of the perpendicular height between a trough and a crest
v Frequency: (Hz) The number of cycles per seconds
v Wave number: ( ν) The number of wavelengths that occupy per 1cm

Wave Theory:

    C = λ. V
  
Particle Theory:






Quantum numbers:
All energy levels are quantized.
Because the energy levels are discrete, transition between energy states only occur when certain energy is absorbed.
There are several transitions that can be investigated such as electronic transition, vibrational transition and rotational transition.
The total energy of a molecule can be written as
ET = Eelec + Evib +Erot+ Etrans




























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