Oxygen K emission spectra of ice, solid carbon dioxide, and solid alcohols

The O K spectra of these 3 products, at -160 Deg, show a prominent peak at 532 eV. In ice and solid MeOH, the principal peak occurs at 526 eV. The ice spectrum has also a well-defined subpeak at 520 eV; it is due to a transition from 1 of the MO. The main band and also the subpeak are broader in MeOH than in ice. The transition at 526 eV results from a 1b1 nonbonding orbital (2pp lone pair) and thus can be called an ionic transition. The O subband at 520 eV stems from a 1b2 bonding orbital (2ps type). The spectrum from solidified CO2 also shows 2 peaks, at 527 and 523 eV, the former one being an ionic peak. EtOH, PrOH, and BuOH yield spectra indistinguishable from that of MeOH.