The commercial purity Succinonitrile (SCN) and para-Dibromobenzene (p-DBB) were distilled using a columnar distillation system. The grain boundary groove shapes for solid SCN in equilibrium with the SCN p-DBB eutectic liquid were directly observed. From the observed grain boundary groove shapes, the Gibbs-Thomson coefficient and solid-liquid interfacial energy have been determined to be (5.47 +/- 0.6) x 10(-8) K m and (8.12 +/- 1.22) x 10(-3) J m(-2) with present numerical method and Gibbs-Thomson equation, respectively. The grain boundary energy of the SCN-rich phase of the SCN p-DBB eutectic system has been determined to be (15.19 +/- 2.58) x 10(-3) J m(-2) from the observed grain boundary groove shapes. The thermal conductivity of the eutectic solid phase and the eutectic liquid phase at the eutectic melting temperature have also been measured to be 0.258 and 0.229 W/K m, respectively. If a comparison is made of the values of Gamma, sigma(SL) and sigma(gb) for SCN based binary organic alloys obtained in the present work with previous work with the same method, it might be then concluded that the value of Gamma depends on the equilibrium temperature and is independent of the equilibrated liquid composition, but the solid-liquid interfacial energy and grain boundary energy both depend on the equilibrium temperature and the equilibrated liquid composition. (C) 2007 Elsevier Inc. All rights reserved.