5.02 | MO Diagram of Cyclopropane and Benzene

Monday June 26th 2023 | In continuation of yesterday’s lesson, we finish by constructing the SAlCs of the Px and Py orbitals of the three carbon atoms. By using analogies to the previous SALCs, we can quickly establish their orientation and determine their symmetry. We also discover that although some Px SALCS do have the right symmetry and energy, the will still not overlap because of spatial constrictions (i.e., the hydrogen atoms happens be at the node of the SALCS). A similar observation was made for Benzene, where we discovered that these SALCS were important for forming the C-C framework, similar to cyclopropane. Overall, we constructed the MO-diagram of both cyclopropane and benzene, where we discovered which orbitals were responsible for C-C, C-H, and π-framework formation.

The link to the video can be found below