4.01 | The MO Diagram of Cyclopropane

Monday July 8th 2024 | In this lecture we looked at the MO-diagram of cyclopropane. Because this is also a molecule that does not contain a central atom, we have to establish the SALCs for both the hydrogen and Carbon Atoms. Although the symmetry of the hydrogen SAlCS is readily established, we realized that because we already know the SALCs for a three-atom system (e.g., NH3 or BF3), we could just take the in-phase and out of-phase combination of the three SALCS to construct the six SALCS generator by the six hydrogen atoms. For the SALCs obtained from the carbon atoms, we first have to establish a coordinate system for each carbon (keeping in mind the symmetry), but thereafter the symmetry of the SALCs is readily established. By using an analogy with “+” and “-“, we could easily establish the SALCS of the px, py, and pz orbitals. With the symmetry of the SALCS established, the MO diagram was generated taking into account the energy and symmetry of all the orbitals and/or SALCS involved. In the second part of the lecture, which is not part of the exam, we used the same principles to obtain the MO-diagram of ferrocene (a metallocene), as practise

The link to the recording of the lecture can be found below: