Torsion angles energy calculations

Calculate the trans and gauche contents in PE at 20, 100, 200, 300, 400 and 600 K. First, consider only first-order interaction, i.e. independent torsion angle energies. Then consider second-order interactions as well, i.e. the interdependence of torsion about two adjacent bonds. Calculate for each case the constant C in the equation o = CnE. 

Figure 5 Calculated potential and potential of mean force of acetic acid along the torsional angle of 0(H—O—C—C). The left-hand side shows the total energies and the components, and the right-hand side shows the decomposed A i into the site.

Calculate the average CCCC torsion angle for the lowest-energy structure of each molecule (use absolute values). Order these structures from most eclipsed to most staggered . Which ring adopts the most eclipsed structure Which ring adopts the most staggered structure ... 

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