One-photon ionization of K2 and Na3

One-photon ionization experiments were performed on K 2 and Na 3 in supersonic molecular beams using a frequency-doubled dye laser and a mass spectrometric detection system. Wavelength scans across the ionization potential of K 2 clearly indicate autoionizing Rydberg levels of low n -values and ungerade symmetry dominating the direct photoionization processes. The ionization of Na 3 , on the other hand, does not exhibit an expressed structure of autoionizing Rydberg states. Possible explanations are discussed.