(37e) Modeling Surface-Anchored Nematic Liquid Crystals for Chemoresponsive Application

Authors: 
Szilvási, T., University of Wisconsin-Madison
Roling, L. T., University of Wisconsin-Madison
Yu, H., University of Wisconsin-Madison
Rai, P., Kent State University
Twieg, R., Kent State University
Abbott, N. L., University of Wisconsin-Madison
Mavrikakis, M., University of Wisconsin-Madison
Surface-anchored nematic liquid crystals can undergo an orientational response to changes in their chemical environment, providing new opportunities for designing selective and sensitive chemoresponsive systems. We have previously shown that the liquid crystal 4-cyano-4â??-pentylbiphenyl (5CB) can be an interesting starting candidate for future sensing applications because its orientational change can be triggered by several important small molecules such as dimethyl methylphosphonate (DMMP), a common component of nerve gas production. The anchoring properties of 5CB also vary greatly with surface-functionality, making it possible to tune the orientational response.1-3We developed a series of theoretical models, based on quantum mechanics, to capture the effect of important experimentally adjustable parameters affecting orientational transitions and formulated an integrated high throughput-like materials discovery approach exploiting the synergistic effects between fast theoretical prediction, synthesis of new liquid crystal materials, and their experimental characterization.

In this presentation, we will show how our new computational models can predict orientational transitions induced by the displacement of liquid crystals by a variety of small molecules. We will summarize how our integrated approach could lead to new, improved candidate materials in several different examples such as detection of NO2, acetone, or ClO2.

1. Shah, R. R.; Abbott, N. L., Science 2001, 293, 1296.

2. Hunter, J.T.; Abbott, N.L., Applied Materials and Interfaces, 2013, 6, 2362

3. Yang, K. L.; Cadwell, K.; Abbott, N. L., Journal of Physical Chemistry B, 2004, 108, 20180.