Editing Rotamer (section)

===Population distribution of conformers===
[[Image:2ConfBoltzmannDist.png|right|thumb|350px|Boltzmann distribution % of lowest energy conformation in a two component equilibrating system at various temperatures (°C, color) and energy difference in kcal/mol (''x''-axis)]]
The fractional population distribution of various conformers follows a [[Boltzmann distribution]]:<ref name="boltz dist">{{cite web|last=Rzepa|first=Henry|title=Conformational Analysis|url=http://www.ch.ic.ac.uk/local/organic/conf/c1_definitions.html|work=Imperial College London|access-date=11 November 2013}}</ref>
:<math> \frac{N_i}{N_\text{total}} = \frac {e^{-E_i/RT}} {\sum_{k=1}^M e^{-E_k/RT}}. </math>

The left hand side is the proportion of conformer ''i'' in an equilibrating mixture of ''M'' conformers in thermodynamic equilibrium. On the right side, ''E''<sub>''k''</sub> (''k'' = 1, 2, ..., ''M'') is the energy of conformer ''k'', ''R'' is the molar ideal gas constant (approximately equal to 8.314&nbsp;J/(mol·K) or 1.987 cal/(mol·K)), and ''T'' is the [[Absolute Temperature|absolute temperature]]. The denominator of the right side is the partition function.