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Updated: Jun 19, 2026

Spatial Separation of Molecular Conformers and Clusters
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Spatial Separation of Molecular Conformers and Clusters

Published on: January 9, 2014

Seven conformers of L-threonine in the gas phase: a LA-MB-FTMW study

José L Alonso1, Cristóbal Pérez, M Eugenia Sanz

  • 1Grupo de Espectroscopía Molecular (GEM), Departamento de Química Física y Química Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47005 Valladolid, Spain. jlalonso@qf.uva.es

Physical Chemistry Chemical Physics : PCCP
|October 20, 2009
PubMed

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In an organic molecule, free rotation about the carbon-carbon single bond results in energetically different conformers of the molecule. Due to this rotation, called the internal rotation, ethane has two major conformations — staggered and eclipsed.
Staggered conformation is a low energy and more stable conformation with the C-H bonds on the front carbon placed at 60°dihedral angles relative to the C-H bonds on the back carbon, leading to a reduced torsional strain. In staggered ethane, the...
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Unlike ethane and propane that have only two major conformations, butane has more than two conformers. The staggered form of butane in which the bulky methyl groups on the two carbons are placed on opposite sides, that is, at a dihedral angle of 180°, is the lowest energy, most stable form — called the anti conformer. This conformation is stabilized due to the absence of steric repulsion between the largely spaced out methyl groups. The other two staggered conformations are degenerate and have...
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Conformations of Cyclohexane

Cyclohexane does not exist in a planar form due to the high angle and torsional strain it would experience in the planar structure. Instead, it adopts non-planar chair and boat conformations.
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