ROTATIONALLY RESOLVED PHOTOIONIZATION OF POLYATOMIC HYDRIDES - CH3, H2O, H2S, H2CO

Combined theoretical and experimental studies of rotationally resolved photoelectron spectra for single-photon ionization of the outermost v alence orbitals of H2O, H2S, H2CO, and CH3 are reported. Agreement bet ween calculated and measured spectra is very encouraging. Both show th at photoionization dynamics is very molecular in origin for H2O, H2S, and H2CO but quite atomiclike for CH3. Parity selection rules and the angular momentum composition of the photoelectron are used to illustra te the dynamical aspects of photoionization of polyatomics as molecula r symmetry changes in a group of structurally related systems.