Kinetic energy dependence of anisotropic yields of ionic fragmentations following S 1s excitations of SO2

Several Sis excited states of SO, are investigated in high-resolution angle-resolved ion-yield spectra using linearly polarized synchrotron radiation. The anisotropy parameter for the triatomic molecule is not directly related to the symmetry of the excited state due to the three-body fragmentation. The present work shows that the symmetries of the lowest three valence states and some low-lying Rydberg states are clearly identified by measuring the kinetic energy dependence of the fragment ion yields at two angles, where the oxygen ion yields are increased and the sulfur ion yields are decreased for the higher kinetic energy. (C) 1998 Elsevier Science B.V. All rights reserved.