Suppose a simple dye molecule can be modeled as having ahydrogen-like energy states with 6 electrons. Initially, theelectrons settle to the lowest total energy state. Imagine that weilluminate this molecule with just right energy to excite theelectrons from the n = 3 level to the n = 5 level. When suchexcited electrons decay back to their lower available energystates, photons of the same energy as the incoming photons areemitted. In addition, photons with different wavelengths can beemitted. This is known as fluorescence. (a) Draw the energy-leveldiagram (for n = 1 to n = 6) and show how electrons are filling theenergy levels before light is illuminated. (b) After theillumination, the electron’s arrangement changes in the energydiagram. Draw the energy-level diagram again (for n = 1 to n = 6)and show how the electrons are filling the energy levels after thelight illumination. (c) The excited electrons in (b) decays to thelower energy states. Identify two transitions producing photonswith longer wavelengths than the incoming photons. Write youranswer in this format: Eph (6 →1), if the photon is generated bythe electron transitioning from n = 6 to n = 1 (this is not thecorrect answer). (d) Explain why other transitions (such as from n= 5 to n = 1) are not possible.
