Question

3. [5] Retinal consists of a chain of carbon atoms roughly 1.5 nm long. Electrons in this long chain molecule behave very much like particles in a box The retinal molecule is a linear molecule that has 12 electrons that are free to move about the chain According to the Pauli exclusion principle, when this molecule is in its ground state, these 12 electrons fill the first 6 states of the box. Thus, the lowest energy photon that can be absorbed by this molecule would be the one that moves an electron from the 6th state to the 7th H3C CH3 [1] What wavelength of light will give rise to this an upward transition? In what part of the spectrum does it fall? [1] In a human eye, there are three types of cones that allow us to see colors. The three different types are most sensitive to red, green, and blue light, respectively. All three contain retinal bonded to a large protein. The way that retinal bonds to the protein can change the length of the potential well within which the electrons are confined. How would the length have to change to make the molecule more sensitive to blue or red light? [3] In general, for a particle in a box, show that the wavelength A of the photon that must be absorbed by an electron to move it from the nth to the (n + 1)th state b. is given by λ,-(2n+1)Th. the particle in the box where L is the length of the box and m is the mass of

Answer 1