The equilibrated grain boundary groove shapes for solid succinonitrile (SCN) in equilibrium with the succinonitrile (SCN) dichlorobenzene (DCB) eutectic liquid were directly observed. From the observed grain boundary groove shapes, the Gibbs-Thomson coefficient and solid-liquid interfacial energy for solid SCN in equilibrium with the SCN DCB eutectic liquid have been determined to be (5.43 +/- 0.27) x 10(-8) K m and (7.95 +/- 0.80) x 10(-3) J m(-2) with present numerical method and Gibbs-Thomson equation, respectively. The grain boundary energy of SCN rich phase of the SCN DCB eutectic system has been determined to be (14.77 +/- 1.77) x 10(-3) J m(-2) from the observed grain boundary groove shapes. Thermal conductivity of eutectic solid phase and eutectic liquid phase at the eutectic melting temperature have also been measured to be 0.269 and 0.231 W/Km, respectively. (c) 2006 Elsevier B.V. All rights reserved.