The TOF distributions were transformed into translational energy distributions, P(ET), where the area under a P(ET) curve is proportional to flux and can be integrated to obtain the total relative flux of the products that correspond to a given TOF distribution collected at a particular combination of θi and θf. Time zero in the TOF distributions of the scattered products is set by assuming a monoenergetic incident beam , with tzero coming from the distance from the nozzle orifice to the sample surface (e.g., tzero = 99.2 𝑐𝑐𝑐𝑐 7918 𝑐𝑐 𝑠𝑠 -1 ). The validity of the monoenergetic beam assumption for this analysis is discussed later. The raw TOF distributions were corrected for the ion flight time given by α ( 𝑐𝑐 𝑧𝑧 ) 0.5 where m is the mass in amu, z is the charge on the ion (an integer), and the parameter, α, was determined empirically . The TOF distributions of O were corrected for dissociative ionization of O2 in the ionizer that came from the small O2 component of the O/O2 beam.