ROTATIONAL BRANCHING RATIOS IN N-2(- OBSERVATION OF PHOTON ENERGY-DEPENDENCE BY PHOTOELECTRON-SPECTROSCOPY() )

Rotational line profiles have been studied as a function of photon ene rgy by use of photoelectron spectroscopy. The relative squared multipo le moment matrix elements of the X (1)Sigma(g)(+) (nu = 0) --> X 2 Sig ma(g)(+) (nu = 0) transition of N-2 have been determined from the rela tive intensities of rotational branches for photon energies between 23 and 65 eV. The; relative intensities, and hence the multipole moment matrix elements of the rotational branches, are clearly dependent on p hoton energy. This non-Franck-Condon-like behavior can be explained by a shape resonance in the 3 sigma(g) --> k sigma(u) ionization channel .