The assumption that the reaction coordinate in going from gauche to anti n-butane is a s...

The assumption that the reaction coordinate in going from gauche to anti n-butane is a simple torsion is an oversimplification, because other geometrical changes no doubt also occur during rotation around the carbon–carbon bond, for example, changes in bond lengths and angles. Examine the energy profile for n-butane (“n-butane” on the precalculated Spartan file) and plot the change in distance of the central CC bond and CCC bond angle as a function of the torsion angle. Are the bond length and bond angle nearly identical or significantly different for the two equilibrium forms of n-butane? Are the two parameters nearly identical or significantly different between the anti form and either or both of the transition states? Explain your results.