ABSTRACT
Let’s consider the simple case of H2, where the distance between the hydrogen atoms (R) is the reaction coordinate, E(R). The PES is then simply a plot of the energy evaluated for various values of R (Figure 1.3). The energy difference between the bottom of the well (the minimum) and the large R asymptote is a measure of the bond strength, and the value of R at the bottom of the well corresponds to the bond length, Re (in general a minimum energy geometry is often called an equilibrium geometry). Both quantities can be measured experimentally, and comparison with experiment tells you how good your theoretical model is.
