Size dependence of critical behavior at smectic-A to nematic transition in random network

The smectic-A to nomatic (AN) transition was studied under confinement as introduced by the randomly interconnected voids of Millipore filters. Using a high resolution calorimetry it was determined that heat capacity peaks evolve from sharp and prominent to broad and small with decreasing void size, The random confinement drives the heat capacity critical exponent from the bulk value towards zero, the 3D-XY modal prediction, indicating a confinement-induced decoupling of smectic and nematic order parameters, Preliminary NMR results show that in the largest Millipore size studied, the behavior is similar to bulk's; in smaller. voids, there are dramatic differences from bulk that emphasize the dominating role that the fibrous surfaces begin io play.