Various possible isomers and conformers for the C8H14 systems were analyzed to calculate the relative stability of each species with reference to the energies calculated at assorted levels of theory - Density Functional Theory (DFT) at the B3LYP level using the 6-31G*,6-31G**, 6-311G* and the highest level of 6-311G+** basis sets is used to evaluate for all the isomers. A total of fifteen isomers with possible conformers (including cis- and trans-) for the C8H14 systems were preferred for the current studyand their structures were shown in figure 3.1. These molecules have been grouped into four major structures: Bridged Head, Fused, Spiro and Isolated Rings. The IUPAC names, structures and short names used for molecules studied from each category in the present work are given in the table below.

DFT at B3LYP level using the highest level of 6-311G+**, Relative Energy and Thermochemistry parameters