The structure of porphine is shown in the figure. To understand the absorption spectra of hemoglobin, one can use a free electron model for a particle on a circle. In the free electron model you may assume that the electrons from the p-orbitals of the carbon atoms populate energy levels derived from the particle-on-a-circle solution to the Schrödinger equation.
A. Assuming that the radius of the circle is 3.5 Å and that the porphyrin has 18 electrons, please draw an energy level diagram for this system.
B. Calculate the maximum of the absorption spectrum (in nm).
lmax = __________________nm.