Near-edge x-ray absorption fine structure spectra of the cis- and trans-
isomers of stilbene in the gas phase reveal clear differences, which are
analyzed by results from density-functional theory calculations using the
transition potential approach. The differences between the two species also
occur in stilbene adsorbed on Si(100), opening the way towards studying
structural changes in molecules in different surface environments, and
configurational switching in organic molecules on surfaces in particular
