Results and the Multiplet Theory

The Nature of Reactants. No less effect on z and e is exerted by the nature of the reacting atoms of the molecule. The values of z and e are distinctly different for hydrocarbons, amines, and alcohols (on the same or similar catalysts). This complies with the multiplet theory of catalysis, according to which in the three reactions the following atomic groups, in which the vertical bonds pass over to the horizontal, are in contact with the catalyst  

In harmony with the multiplet theory is the observed dependency on the nature of the catalyst, since the atoms of the latter are involved in the multiplet complex. 

The Influence of Substituents. The substituents at the groups indicated have a markedly smaller effect on z and t. This is evidence for the orientation of the molecules with their reacting atoms toward the catalyst (Fig. 13), as is required by the theory. The influence is particularly slight in the case of metals. For hydrocarbons (Nos. 1-3), amines (23-29), and alcohols Z — 1 and z3 = 0. From a crisscross examination of the data of Nos. 40-47, it can be seen that in the case of copper not only the values of z2 but also those of a2 are practically the same for ethyl, n-propyl, isopropyl alcohols, acet- and propionic aldehydes, and also acetone. This was explained by the author (66) in a treatment of the above-mentioned model from the standpoint of statistical mechanics. It was found that 

The activation energy t for the cyclic hydrocarbons on Ni—AI2O3 are practically independent of the number of methyl side groups (Nos. 1-3). For amines on Ni and Pd (Nos. 23-39) the are also quite constant. 

In the case of oxides z3 0. For MnO and isopropyl alcohol z3 increases from 0.1 at 316° to 0.36 at 366°. The substituents exert a stronger influence on z2 Thus, on Cr2Os, 22 has a tendency to increase with the methyl 

---