The average error of the RCE is 9.75 % (for the individual RCE values see table 10 and figure in section 5). The average error for the RCE is calculated by adding all individual errors and dividing the sum by the amount of RCE. If the (absolute) error for the target RCE based on MP2.5/AVTZ's reproduction of CCSD(T) results (Table of reference ) is estimated, the upper limit was -0.012 kcal • mol -1 as computed for n-hexane (i.e., 12 conformers). This results in an average relative error of -0.91 % and the herein achieved results and error ranges are not as good as those results and error ranges. However, considering the different theories (i.e. MM vs. CCSD(T) or MP2.5/AVTZ calculations) and the required time to compute the results, the average relative error range of 9.75 % achieved herein is acceptable. It is worth noting that this level of error is similar when comparing 96 Density Functional Theory (DFT) (B2K-PLYP-D) computed octane values to MP2.5/AVTZ values, which has an error of +0.19kcal • mol -1 (i.e., 9.43 %) .