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The concurrent ion–molecule reactions in mixtures of HCl and HCN with D2and CD4have been studied by the ratio plot method. The following reactions have been detected in mixtures with HCN and their cross sections determined at 10.5 V cm−1repeller field strength.In mixtures of D2and CD4with HCl the following reactions have been detected and cross sections determined.Rate constants for the self-reactions in HCN and HCl have been measured both at 10.5 V cm1repeller field and at thermal ion energies.

The ion–molecule reactions occurring in CH3SH and CD3SH have been identified and rate constants measured for ions of 3.4 eV ion exit energy. The reaction CD3SH+ + CD3SH involves predominantly transfer of the mercaptyl hydrogen.

Trideuteromethyl radicals have been reacted in the vapor phase with allyl formate and the principal reaction over the temperature range 100–250 °C has been shown to be the displacement reactionHydrogen atoms generated by this decomposition also react readily to produce propylene by the reaction

The following ion–molecules reactions have been found to occur in DCOOH for ions produced by bombardment with electrons of 10–15 eV energy (all rate constants in cm3molecule−1units).In methyl formate the following reactions have been identified and rate constants measured for ions formed by bombardment with electrons of 10–15 eV energy.Experiments using DCO2CH3show that reaction [f] involves transfer of the methyl hydrogen at a rate 1.5 times that of the formyl hydrogen while reaction [g] involves transfer from only the methyl position of CH3OH+. The rate constants for all reactions are considerably higher than predicted on the basis of ion–induced dipole interactions only but are in good agreement with values calculated by including ion–dipole interactions.

The rate constants for the hydrogen-transfer ion-molecule reactionshave been measured at thermal ion energies and found to be 12 × 10−10 cm3molecule−1s−1and 8.0 × 10−10 cm3molecule−1s−1respectively. The rate coefficients at higher ion energies (3.7 eV ion exit energy) show little change from these values. Reactions [a] and [b] have also been studied using CD3OH and it is found that in reaction [a] the hydroxyl hydrogen is transferred 2.5 times more readily at low ion energies and 1.8 times more readily at high ion energies than a methyl hydrogen. This rather small specificity would appear to preclude formation of a "locked-in" collision complex even at low ion energies.