constitutes a fast method. Mixtures
of conformers can sometimes be detected in PE spectra if orbital
energies depend on a parameter of the conformational change, e.g.
a dihedral angle, and differences in orbital energies of
conformers are large enough. In such a case, there are usually
more ionization bands in the low energy part of the PE spectrum
than there are orbitals in the molecule from which the ionizations
could arise. The measured spectrum for 1 is not of this