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Publication costs assisted by the Hahn-Meitner-lnstitofMethanol radicals CH20H react with oxygen and produce peroxy radicals 02CH20H, ~C I *~O H + O~ = (4.2 I 0.5) X lo9 M-l sec-l. OzCHzOH ionizes to form 02CH20-which quickly decomposes to CHzO and 02-.The ionization is catalyzed by OH-and by HP0d2-. k02CH20H+OH-= (1.8 f 0.9) X 1Olo M-' sec-' and ~O~C N~O H + H~O~Z -2 X lo6 M-l sec-l were measured. The spontaneous ionization rate constant ~o~c H~~H -~~~H~~-+ H + < 3 sec-l was estimated. The pK of O2CHzOH was estimated to be higher than 6, and probably >8.8. Previous reports of more accurate determinations of pK values of peroxy radicals should be reconsidered, in view of the possible instability of the basic form of the peroxy radicals. The absorpticm spectrum of 02CH20H was determined. E 1070 M-l cm-l was measured at 248 nm. At relatively high pulse intensities, formation of 0 2 -from O2CH2OH is inhibited, and a second-order process which competes with the unimolecular formation of 0 2 -from 02CH20-is proposed.

Publication costs assisted by the Hahn-Meitner-lnstitutThe catalytic effect of Cu2+ in enhancing the dismutation of the peroxy radicals HO2 and O2-has been investigated. Cu2+ ions react with O2-(k = 8 X 10® M-1 sec-1) and with HO2 radicals (k s 1 X 108 M-1 sec-1). The catalytic effect involves alternate reduction and oxidation of the copper. Cu+ reacts with O2-with a rate constant of ~1010. HO2 oxidizes Cu+, k > 10® M-1 sec-1. The uv absorption spectrum of Cu+ has been measured in formate and in methanol solutions.

The reactivities of Cu(II) complexes, including formate, ammonia, Cl-, SO42-, and some amino acids, toward 02~were investigated in the presence of excess of the complex forming additives. The reactivity of the Cu(II) complexes is substantially smaller than that of free Cu2+ ions, when several ligand molecules are attached.

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