Hyperconjugation not steric repulsion leads to the staggered structure of ethane

@article{Pophristic2001HyperconjugationNS,
  title={Hyperconjugation not steric repulsion leads to the staggered structure of ethane},
  author={Vojislava Pophristic and Lionel Goodman},
  journal={Nature},
  year={2001},
  volume={411},
  pages={565-568}
}
Many molecules can rotate internally around one or more of their bonds so that during a full 360° rotation, they will change between unstable and relatively stable conformations. Ethane is the textbook example of a molecule exhibiting such behaviour: as one of its two methyl (CH3) groups rotates once around the central carbon–carbon bond, the molecule will alternate three times between an unstable eclipsed conformation and the preferred staggered conformation. This structural preference is… Expand
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