First LEPS surface

This first Leps surface gives the best overall picture but is not sufficiently resolved for a location of the 'Transition State'. The entry valey of the reaction is top-left. The barrier is a late one, lying in the exit valley. Therefore, the potential surface is called 'repulsive' in the reaction direction H₂ + Br Þ H + HBr.- Leps.exe allows to choose by mouse movement a rectangular cut around the approximate locus of the TS at the cross. In the next frame this cut is enlarged. This is continued until the side of the grid is of the order 10^-5 to 10^-6 Ångstroms, when the surface has become 'harmonic' around the TS.