Orientational dynamics in supercooled liquids near T-c and comparison withideal mode-coupling theory

Orientational dynamics in supercooled salol and ortho-terphenyl were measur ed near their critical temperatures, T-c, with optical Kerr effect experime nts spanning a very broad range of times. Above T-c, the decays are shown t o be in excellent agreement with the master curve predicted by ideal mode-c oupling theory when higher order terms are included. Between the critical d ecay and the von Schweidler power laws, the intermediate time range of the data can be modeled by a power law. This intermediate power law, located at 2 < t < 10 ps to 500 ps (depending on temperature), shows a significant te mperature dependence with a power law exponent of similar to-1 below T-c.