Statistical analysis of the conformations and isomeric equilibria of hexanes, heptanes, octanes and nonanes

Abstract

Literature data on the equilibria between lower alkane isomers have been treated according to a simple statistical analysis of the conformational energies. The equilibrium ratios of isomers with the same degree of branching are reasonably consistent with a small set of general conformational statistical weights, which are also in good agreement with those used in the conformational analysis of polyalkenes. Equilibrium ratios of isomers with different degrees of branching are predicted very poorly by the simple theory. This disagreement is probably due to differences in vibrational and electronic partition functions.