Values for the gas-phase thermodynamic functions of conjugated compounds existing as a mixture of conformers

Abstract

The conformational analysis of trans-but-2-enal, propenal, propenoyl chloride, propenoyl bromide, ethanedial, ethanedioyl chloride, and ethanedioyl bromide has been summarised. Values for the entropy, heat capacity, and enthalpy (H^⊖–H₀^⊖/T) have been calculated for all these compounds in the gaseous phase, except ethanedioyl bromide, over a range of temperatures by statistical methods, allowing for increase in these values due to mixing of low and high energy conformers. The concentration of high energy conformer at each temperature has been calculated.