Online Condensed Matter Seminar (February 1, 2021), Department of Physics, Case Western Reserve University (Host: Phil Taylor).
Speaker: Mesfin Tsige (School of Polymer Science and Polymer Engineering, The University of Akron)
Abstract: There is a tremendous need for a greater understanding of the properties of matter at surfaces and interfaces at the nanometer scale mainly driven by the unprecedented impact of nanoscale materials in current industrial products. It is well known that matter behaves in complex ways and exhibits exotic properties at nanometer length scales. However, understanding the behavior of matter at such length scales using experimental methods has in general been very difficult. Computer simulations have proven very useful in predicting properties of novel materials yet to be synthesized as well as predicting difficult to measure or poorly understood properties of existing materials. In my group, we use multiscale modeling and simulation methods and theoretical approaches to interrogate the behavior of small molecules and polymers at surfaces and interfaces. In this talk, I will present and discuss our recent results on the spontaneous spreading of liquid droplets on solid substrates which is a classic wetting problem and is also a subject of great technological importance. Towards that end, we modeled, for the first time, the spreading of water droplets on a completely wetting surface where the kinetics of spreading is controlled by hydrogen bonding between substrate and water molecules. Interestingly, the dynamics of the water droplets at the nanoscale has been found to be described by a first-principles model based on the hydrodynamic theory that was developed for describing experimental wetting data.
