Photoionization of CO -CO-O Mixtures. Formation and Reactions of Ion Clusters.

Various mixtures containing combinations of CO, O, or CO have been photoionized at 16.7 and 21.2 eV at pressures up to 1.5 torr in the NBS high pressure photoionization mass spectrometer. In CO-CO mixtures the interactions of ions eventually lead to the formation of and [(CO)CO] cluster ions, while photoionization of CO-CO-O mixtures yields mainly oxygen-containing clusters at higher pressures. The investigation of O-CO mixtures also revealed reactions between and CO. The role of impurity reactions involving HO is considered in some detail, and the implications of all of these data to the vapor phase radiolysis of CO is discussed.