Chiral and steric effects in ethane: A next generation QTAIM interpretation

We introduce a development of next generation quantum theory of atoms in molecules (NG-QTAIM) for an investigation of the chirality of ethane. A new isomer type Q(sigma) is discovered in addition to S-sigma and R sigma stereoisomers in the stress tensor trajectory U-sigma-space. The Q(sigma) isomer is defined to be a 'null-isomer' since the value of the chirality-helicity function approximate to 0. The presence of chiral contributions suggests that steric effects, rather than hyper-conjugation, explain the staggered geometry of ethane. The steric effects, within the NG-QTAIM interpretation, are reduced by a factor of two using an electric-field directed down a C-H bond.

Automated summary

This paper introduces a new development in the investigation of the chirality of ethane using the next generation quantum theory of atoms in molecules (NG-QTAIM). A new isomer type Q(sigma) is discovered and defined as a 'null-isomer'. The study suggests that the staggered geometry of ethane can be explained by steric effects rather than hyper-conjugation. It also finds that the application of an electric field can reduce the steric effects.