Hydrogen Atom-formaldehyde Reaction
نویسندگان
چکیده
where H-H-C and H-D-C are weak bonds and make a negligible contribution, leads to a value of -2 kcal. Therefore, E5-E2=1 kcal compared with the experimental value of 1.0 kcal. The preexponential factor for this pair of isotopic reactions can be calculated from the difference in the entropies of activation. Using the same loose complex as above and applying the expression derived by Bigeleisens for the calculation of entropy differences between isotopic molecules, a value of 0.8 is obtained for A2/ A 5, 1.1 being obtained experimentally. The 8 J. Bigeleisen, J. Chern. Phys. 21, 1333 (1953).
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