Structural Chemistry

, Volume 20, Issue 1, pp 43–48

Quantum chemical analysis of the energetics of the anti and gauche conformers of ethanol

Original Research

DOI: 10.1007/s11224-008-9395-7

Cite this article as:
Scheiner, S. & Seybold, P.G. Struct Chem (2009) 20: 43. doi:10.1007/s11224-008-9395-7


Ethanol displays two stable conformers, the classic anti (or trans) form and a gauche conformation in which the hydroxyl hydrogen points toward one of the methyl hydrogens. Surprisingly, the two forms have nearly equal energies, and in the vapor phase the gauche form predominates because of its twofold degeneracy. An analysis of the energetics of these conformers based on natural bond orbital analysis helps to explain the apparently anomalous near degeneracy of these conformers.


Rotamers Lone pairs NBO Charge transfer 

Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  1. 1.Department of Chemistry and BiochemistryUtah State UniversityLoganUSA
  2. 2.Departments of Chemistry and BiochemistryWright State UniversityDaytonUSA