Potential energy profile diagram

Figure 1. Potential energy profile diagrams for a charge transfer process as in ion discharge with coupled atom transfer (based on representations by Gurney and Butler L In (b), curve / represents the H /H20 proton interaction potential and m that for discharged H with the metal M. R is the repulsive interaction of H with H2O and A the resultant interaction curve for H with M.

The reaction of G2 with E2 to form 2EG is exothermic, and the reaction of G2 with X2 to form 2XG is endothermic. The activation energy of the exothermic reaction is greater than that of the endothermic reaction. Sketch the potential energy profile diagrams for these two reactions on the same graph. 

Figure 4. Morse-type potential energy profile diagram for proton transfer showing region where proton energy levels in initial and final energy wells become equal to each other.

A potential energy diagram for nng inversion m cyclohexane is shown m Figure 3 18 In the first step the chair conformation is converted to a skew boat which then proceeds to the inverted chair m the second step The skew boat conformation is an inter mediate in the process of ring inversion Unlike a transition state an intermediate is not a potential energy maximum but is a local minimum on the potential energy profile... 

Graphical representation of the saddle point (here marked with an X) for the transfer of atom B as the substance A-B reacts with another species, C. Potential energy is plotted in the vertical direction. Note also that the surface resembles a horse saddle, with the horn of the saddle closest to the observer. As drawn here, the dissociation to form three discrete species (A + B J- C) requires much more energy than that needed to surmount the path that includes the saddle point. A two-dimensional "slice" through a saddle point diagram is typically called a reaction-coordinate diagram or potential-energy profile. 

It is possible to use the 3-D surface with its corresponding 2-D contour diagram and potential energy profile to discuss the general reaction A + BC —> AB + C where A, AB, BC and C are all polyatomic molecules. 

Figure 1.4 A schematic diagram of chemical potential changes at the stationary occurrence of a stepwise reaction R Yq Y2 P, where R and P are the initial reactant and final product of the reaction, while Yq and Y2 are thermalized Intermediates. The minimums in the traditional potential energy profile relate to the standard chemical potentials of thermalized external reactants and intermediates. However, actual chemical transformations of the intermediates occur at stationary values Pyi and pvz (bold lines), the rates of these transformations being dependent on the difference of the corresponding thermodynamic rushes and the values of truncated rate constants e-,j (the latter are functions of standard chemical potentials of the transition states only).

Sketch the potential energy profile for the reaction between propanone and iodine. Simplify the diagram by combining the fast stages into one combined second stage. 

Figure 4. Schematic diagram to show the reorganization energy X for nonisotopic reactions for harmonic free energy profiles. This figure shows a normal region activation barrier when-AG° < an activationless situation when -AC =. l.and an inverted region activation barrier when-AG° > A for the harmonic potential inii andGfin represent the initial (reactant) and the final (product) system free energy, respectively.

---