Conformational properties ofn-alkanes

Values of the conformational entropy contributionΔSc to the melting entropyΔSm are calculated from a recently reported equation of state (Jain and Simha), and compared with theoretical valuesSc derived from the rotational isomeric state approximation. For the shortern-alkanesΔSc is considerably larger thanSc, whereas for the longern-alkanes the conformational entropy contribution can approximately be described with the rotational isomeric state model. Equations are presented for the calculation of specific volumes at the melting temperature as a function of chain length.