Question

For the Portfolium, the assignment is the same assignment you were given at the start of the semester on chapter 7 Now though, you need to answer the same questions diagrammatically as I did in lecture. See your lecture notes. You need to indicate absorption, say from a lower energy level to a higher energy level. Then indicate emission for the same transition as through various pathways, which would then result in many more emission peaks than was in the original absorption (transition).

Answer 1

In the below diagram, during the absorption, the system is in its lowest energy state i.e. ground state (n=0). Lowest energy of ground state is represented as lowest vibrational level as $\nu$ =0. Upon absorption of a photon the system occupies excited state (n=1). The molecule then deexcited to its lowest vibrational state of the excited state i.e n=1 and $\nu$ =0. This is called vibrational relaxation and donot contribute in emission spectra. Though, this serves as the spectral shift between absorption and emission spectra. Thereafter, the molecule deexcites via emission of light to various vibrational levels of ground state followed by vibrational relaxations. Thus, multiple spectral lines may appear for single absorption line in a given system. The diagram shows three such lines.