The movie below illustrates the isomerization of HCN to CNH. The plot on the right side illustates MacMolPlt's abilty to graph energies and structural features along a reaction path. In this example the blue curve indicates the energy and the purple curve indicates the C-N bond distance. The red dots indicate the value for the currently displayed geometry. The left hand axis indicates the range in energy while the right hand axis indicates the range in the bond distance. Note that the units on the energy plot default to Hartrees, but may be automatically converted to kcal/mol relative a user specified zero point, here the zero was set to the reactants energy.