To further assess the physical properties of I-III, viscosity measurements were performed on chloroform solutions of I-III using a micro-Ostwald viscometer. A double-logarithmic plot of the specific viscosity versus concentration was obtained (Fig. ). (Z)-I exhibited only minor changes in viscosity between concentrations 4 mM-24 mM with a slope of ~ 1.0, suggesting small cyclic species were present. Above 24 mM the slope increased to ~ 1.5, indicating an increase in molecular weight. The viscosities of (E)-I increased steadily with concentration with a slope of 1.2, indicative of concentration dependent oligomerization -an inflection in the double-logarithmic plot denoting a switch in ring-chain bias is more difficult to perceive.