TWO- AND THREE-PHOTON ABSORPTION STUDIES OF THE $O_{2}$ MOLECULE

Abstract

Author Institution: Department of Chemistry, Yale UniversityResonance enhanced multiphoton ionization studies in the 275-330 nm region reveal a large number of 2- and 3-photon transitions to previously unknown states. We have analyzed, in detail, four vibrational components of a rotationally resolved electronic transition at 8.2 eV. The vibrational frequency of $1870 cm^{-1}$ and a rotational constant of $1.68 cm^{-1}$ suggest that the upper state is the lowest Rydberg state (3s$\sigma$) of $O_{2}$. The rotational structure is consistent with an electronic designation of $^{3}\Pi_{0_{g}^{-}}$ for this state