Principle of UV -visible Spectroscopy

Principle of UV visible spectroscopy

Principle of UV -visible spectroscopy states that the absorption of electromagnetic radiations in the UV and visible region excites the electron from lower electronic level to higher electronic level called as electronic transitions. Since it involves electronic transitions, it is also known as electronic spectroscopy.

The electronic transitions are also accompanied by vibrational and rotational transitions.

The amount of light absorbed is given by Beer-Lambert's law which states that:

logI0/I = A = Ɛcl

Where,

I0 = intensity of incident light

I = intensity of transmitted light

A = Absorbance

Ɛ = Molar absorptivity Coefficient or extinction Coefficient

c = concentration

l = path length

Comments

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Chemistry Notes for B.Sc. and M.Sc.

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