loi de Beer Lambert

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Bonjour,
quels sont les 5 critères qui permettent de valider la loi de Beer Lambert?
Merci
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je cite wikipedia en partant du principe que tu sais parler anglais (sinon je peux traduire).

There are at least five conditions that need to be fulfilled in order for Beer’s law to be valid. These are:

1. The absorbers must act independently of each other;
2. The absorbing medium must be homogeneously distributed in the interaction volume and must not scatter the radiation;
3. The incident radiation must consist of parallel rays, each traversing the same length in the absorbing medium;
4. The incident radiation should preferably be monochromatic, or have at least a width that is more narrow than the absorbing transition; and
5. The incident flux must not influence the atoms or molecules; it should only act as a non-invasive probe of the species under study. In particular, this implies that the light should not cause optical saturation or optical pumping, since such effects will deplete the lower level and possibly give rise to stimulated emission.

If any of these conditions is not fulfilled, there will be deviations from Beer’s law.