rsltely deter^^^^^^ 440 ,396 eV (239.8 kcal/m01)'~ Paulett and Ettinger is twice as large as the parennt ion, from svhich GaR f G ( O G 2 60.6 kcal/mol is ob- whereas our data show that the C 2* peak is C J I I 66' ~ ~7, taiaaed of the parent. The other peak ratios are quite corn~ o ~ b ~ the n ~ remits n g from the three independent parable. It is therefore possible that extenkve p y d processes ali0.il.s u , ~io place a lower limit for ANfO0(cysis may have taken place in their reaction c h a ~ ~ e r I. The fact that the heat of to produce CH2 $- N2 prior to ~ o ~ The ~ ap-~ a resulting from the measured pearance potmtial of 11.0 e'V which they rrieas11re may I, and 111 all lie within 1 kcall be due t o ''free" CH2, which. leads bo a much higlaer value of AH?" (c-GH,N2). The result^ re s ~ ~ ~ ~ icative that the true value of e to our lower l i m k As prein Table 11. dvukdfml if ~ ~ ~ ' ~i s * ~~ ~c ~ -c ~~ o ~ I ~ ~authors ~ ~ ~~ ewould ~ n ~t like w ~The . to thank f'(c -CHZK2)obtained ry Dr. L. Wayne Sieck of the Physical ~ h e m ~ s t Division ~ ~ r ~ (79 ~ 3 7~~~~~~~o~~ ~ ~ ~bys electro~i ~ y impact8 is defifor: performing the photoionization e ~ ~ e ~ ~ ~ e n t s . nitely outside +iflhi. ;ibo.ve limits. From Table I, it is agzpmnt Lhst lii- 1114, (m/e 14) peak obtaincd by (19) 6.Hersberg, Can. J. Phys., 39, 1511 (1961).
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