PHOTOIONIZATION MASS-SPECTROMETRIC STUDIES OF THE ISOMERIC TRANSIENT SPECIES CD2OH AND CD3O

Both CD2OH and CD3O were prepared in situ by the reaction of F atoms with CD3OH, and studied by photoionization mass spectrometry. The adiabatic ionization potential (I.P.) of CD2OH was found to be 7.540 +/- 0.006 eV, in good agreement with the photoelectron spectroscopy (PES) value, 7.55 +/- 0.01 eV. However, the adiabatic I.P. of CD3O was determined to be 10.726 +/- 0.008 eV, in marked contrast to the PES value for CH3O, 7.37 +/- 0.03 eV, but in the expected range based on reported values of DELTA-H(f)o(CH3O+) and DELTA-H(f)0(CH3O). From selected values of DELTA-H(f0)0(CH2OH+) less-than-or-equal-to 172.0 +/- 0.7 kcal/mol and DELTA-H(f0)0 (CH3O) = 5.9 +/- 1.0 kcal/mol, we deduce DELTA-H(f0)0 (CH2OH) less-than-or-equal-to - 2.1 +/- 0.7 kcal/mol and DELTA-H(f0)0 (CH3O+) = 253.1 +/- 1.0 kcal/mol.