sentence: Light can move an electron up to an excited state that occupies a higher orbital.
sentences_after: The excited electron will occupy the LUMO, which has a higher energy level than the electron's old orbital. If light opens the ring of 3,4-dimethylcyclobutene, the resulting electrocyclization would be occur by a disrotatory mode instead of a conrotatory mode.
concept_name: light
headings: Electrocyclic reaction Excited state electrocyclizations
categories: Chemistry