Abstract
High-resolution ac calorimetric studies show that the dispersion of 70-Å-diameter hydrophilic silica spheres (aerosils) has a substantial effect on several liquid-crystal transitions in butyloxybenzlidene octylaniline (4O.8). The weakly first-order nematic –isotropic the second-order nematic –smectic- and the strongly first-order smectic-–crystal- freezing transition all exhibit shifted transition temperatures and substantial changes in the shape of excess heat capacity peaks. Power-law fits show an evolution of the critical exponent α from in bulk 4O.8 toward in suspensions with silica densities For the peaks are rounded in a manner qualitatively like those for 4O.8 confined in a high-porosity aerogel, one of which was also studied.
- Received 28 April 1997
DOI:https://doi.org/10.1103/PhysRevE.56.3044
©1997 American Physical Society