High resolution single-photon ionization of HBr in the spin-orbit autoionization region

Irrgang R, Bowering N, Drescher M, Spieweck M, Heinzmann U. High resolution single-photon ionization of HBr in the spin-orbit autoionization region. JOURNAL OF CHEMICAL PHYSICS. 1996;104(22):8966-8972.The rotationally resolved photoelectron yield in the ionization of jet-cooled HBr was measured in the energy range between the spin-orbit split (2) Pi ionic thresholds. For single-photon excitation, narrow-band VUV radiation was generated by resonant frequency mixing. The spectrum is complex due to interaction of autoionizing resonances belonging to several series converging to different rotational states of the ion core. For low Rydberg orders, n less than or equal to 11, a description of angular momentum coupling according to Hund's case (c) is found to be appropriate. An assignment of higher Rydberg series in the range of 17 less than or equal to n less than or equal to 20 was made in Hund's case (e) coupling scheme by comparison with the corresponding photoionization spectra of Kr, HI, and HCl. (C) 1996 American Institute of Physics