The pentacyclic hydrocarbons 4-7 have been prepared from homocuneone (9) and theii photoelectron spectra have been recorded. In each instance, it has proved possible to assign the first five bands, reliance being placed upon a 2130 model and comparison with related compounds. The matrix elements for the through-space interaction between the dicyclopropyl fragment and the structural unit at the 9 position were determined to be the ...