Bond dissociation energy of O2 measured by fully state-to-state resolved threshold fragment yield spectra.

We have determined the bond dissociation energy of O2 by measuring fully state-to-state resolved threshold fragment yield spectra in the XUV energy region, O2X3Σg-,N″,J″→O(PJ3)+O(S1o3)/O(S2o5). Our results have yielded a bond dissociation energy value of 41 269.19 ± 0.10 cm-1, which is consistent with previous measurements but exhibits a significantly lower uncertainty, approximately five times smaller. It is noteworthy that this study is the first to simultaneously achieve fine structure state resolution for the parent O2 molecule and spin-orbit state resolution for the O(3PJ) fragments in the measurement of O2 bond dissociation energy. As a result, our findings have established a solid foundation for the obtained data.