Piperidine: vibrational assignment, conformational analysis, and chemical thermodynamic properties.
J Chem Thermodynamics 1971 Sep; 3(5):649-656
Interpretation of the molecular spectra of piperidine with the aid of a molecular vibrational analysis showed that the molecule exists mostly in the equatorial conformation in the vapor state and exclusively so in the crystalline state. An energy difference of about 0.6 kcal mol-1 between the axial and equatorial conformations was found consistent with calorimetric data. A table of the chemical thermodynamic properties has been compiled.
OP; Journal Article
The Journal of Chemical Thermodynamics