This applet (from
the iridum project) covers an aspect of the Physical Chemistry
spectroscopy course that students often find confusing. Although it is
based on relatively simple mathematics, a complete understanding of the
phenomenon requires assimilating the following concepts:

- The energy levels of a diatomic molecule are given by the formula:
- E(v,J) = hv (v + ½) + BJ (J + 1); v = 0..infinity, J=0..infinity
- A molecule absorbs light at frequencies that correspond to difference between energy levels. In this case, we are interested in the following differences, frequency of light:
- E (v = 1, J') - E (v = 0, J); with J' = J + 1 or J -1
- The intensity of the transition is proportional to the population of the lower state, intensity is proportional to:
- J (J + 1) exp[-E (v = 0, J) / kT]

Auf diesem Webangebot gilt die Datenschutzerklärung der TU Braunschweig mit Ausnahme der Abschnitte VI, VII und VIII.