In the previous problem and the associated molecular model at the book's website, you considered the role

Question:

In the previous problem and the associated molecular model at the book's website, you considered the role of HOMOs and LUMOs in an SN2 reaction.
(a) What is the LUMO in an SN1 reaction and in what reactant and species is it found?
(b) Open the molecular model at the book's website titled "Isopropyl Methyl Ether Carbocation LUMO." Identify the lobe of the LUMO in this carbocation model with which a nucleophile would interact.
(c) Open the model titled "Isopropyl Methyl Ether Carbocation HOMO." Why is there a large orbital lobe between the oxygen and the carbon of the carbocation?