Determination of Surface Tension of Succinonitrile Using a Surface Light Scattering Spectrometer

Liquid vapor iInterfacial surface tensions of succinonitrile, NC(CH2)2CN, were measured using noninvasive surface light scattering (SLS) spectroscopy. Suc- cinonitrile (SCN) has been and is being used extensively in materials science and fluid physics research, for example, in several theoretical and numerical studies of dendritic growth. It is an established model material with several essential physical properties accurately known with the exception of the liquid vapor surface tension, #lv , at various temperatures. Using the SLS spectrometer, we have experimentally determined the liquid vapor surface tension of SCN in the temperature range from just above its melting point (58.1%C) to 118%C using this noninvasive method. Previous measurements of SCN surface tension are extremely limited. To the best of our knowledge, this work is the first to measure the surface tension of succinonitrile noninvasively at melt and elevated temperatures. The SLS spectroscopy is relatively new and unique. This techni- que has several advantages over classical methods: it is noninvasive, has a good accuracy, and can be used to measure the surface tension and viscosity simulta- neously, although the viscosity results are not discussed here. The accuracy of values obtained from this technique on some standard liquids is better than 20 for the surface tension and about 10 to 150 for viscosity. Our measurements gave #lv=42.28&0.0629T\0.2 (mN} m&1), with T in %C, and the viscosity at 60%C is 2.68\0.3 cp for pure SCN.