Ion-molecule studies of energetic oxygen allotropes in flow tubes: O₂ (v), O₂ (a???????¹?g), O₃ , and O?

Starting in the 1960s, flow tube apparatuses have played a central role in the study of ion-molecule kinetics, allowing for immense chemical diversity of cationic, anionic, and neutral reactants. Here, we review studies of oxygen allotropes, excluding ground state O-2 ((XSg-)-S-3 ), and focusing instead on reactions of cations, anions, and metal chemi-ionization reactions with ground state atomic oxygen (O 3P), vibrationally excited molecular oxygen (O-2(v)), electronically excited molecular oxygen (O-2 (a???????(1)?(g)) ), and ozone (O-3). Historical outlines of work over several decades are given along with a focus on more recent work by our group at the Air Force Research Laboratory.