MOLECULAR MOTIONS IN A VISCOUS ORGANIC LIQUID : FERROCENE IN COLD BUTYL PHTHALATE

Abstract

The two main purposes of this work were to learn if : a) rotational diffusion could be seen along with translational, and b) to clarify the gain in < x2 > as the glass was heated. Our observations show that : a) rotational molecular diffusion is not likely ever to be observed by Mössbauer technique and b) that there is indeed a fast increase in < x2 > above Tg. This increase is correlated with a rapid and linear increase of the number of soft modes for the liquid above the glass transition temperature