Most of the concern in isomerism is due to the conformational isomers due to torsional points around single bonds since almost all the conformational isomers are energetically accessible and populated to some extent. Thus, the number of torsion points defines (and mostly limits) the number of conformational isomers to be sampled to get more accurate energetics of the molecule. The best scenario in examining low energy lying conformations is to calculate all possible conformations systematically and then find all local minima along with the global minimum structure.