High resolution spectral analysis of oxygen. IV. Energy levels, partition sums, band constants, RKR potentials, Franck-Condon factors involving the X³Σg⁻, a₁Δg and b¹Σg⁺ states.

We have updated the isotopically invariant Dunham fit of O2 with newly reported literature transitions to derive (1) the energy levels, partition sums, band-by-band molecular constants, and RKR potentials for the X(3)Σg(-), a(1)Δg, and b(1)Σg(+) states of the six O2 isotopologues: (16)O(16)O, (16)O(17)O, (16)O(18)O, (17)O(17)O, (17)O(18)O, and (18)O(18)O; (2) Franck-Condon factors for their a(1)Δg-X(3)Σg(-), b(1)Σg(+)-X(3)Σg(-), and a(1)Δg-b(1)Σg(+) band systems. This new spectroscopic parameterization characterizes all known transitions within and between the X(3)Σg(-), a(1)Δg, and b(1)Σg(+) states within experimental uncertainty and can be used for accurate predictions of as yet unmeasured transitions. All of these results are necessary to provide a consistent linelist of all transitions which will be reported in a followup paper.