A POTENTIAL ENERGY MODEL FOR DISPLACEMENT REACTIONS NORMAN S. MacDONALD Occidental College, Los Angeles, California
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VERY COMMON type of chemical reaction is the displacement reaction X YZ-+XY Z , \\-here the let,ters may represent atoms or groups of atoms with or without charge. While conducting a course dealing \\-ith some theoretical aspects of organic chemistry, it was foreseen that a model of a typical potential energy surface for a triatomic system would be of value. Such a model serves as a concrete object upon which a number of theoretical discussions may he focussed for the edification of the student. The purpose of this communication is to describe the construction of such a t,hree-dimensionalmodel and t o point out its utility in the classroom. Historical Background:. In 1929 an empirical equation was proposed by Morse (I) which expressed the potential vibrational energy of a diatomic molecule as a function of the internuclear distance.
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