(Scanned original: to be superseded.)

ESDU 86023 gives heat capacity and enthalpy data for 34 alkenes and 9 alkadienes tabulated at 10 K intervals between the normal melting point and 0.96 critical temperature along the saturation line. The data were obtained by fitting a polynomial equation to experimental data for heat capacity for each compound taken from a wide range of sources in the literature; the constants of the equation were also faired with molecular structure for compounds that were members of the same chemical series. The enthalpy values were obtained by integrating the specific heat polynomial for each compound. The coefficients of the equations are tabulated together with values of critical temperature and normal melting point of each compound. An estimation of the accuracy of the predictions is included.