Start
Jul 28, 2016 - 17:00
End
Jul 28, 2016 - 18:00
Venue
Room 118 Chemical Engineering
Event Type
Speaker
Dr. Ronald Benjamin Soft Matter Institute Heinrich-Heine University Duesseldorf Germany
Title
Investigating solids and liquids at interfaces via novel Molecular Simulation Techniques
Abstract: The free energy of an interface formed between two condensed phases such as a crystal and its melt or between a condensed phase and a solid substrate is an important parameter governing the growth and nucleation of a crystal from its melt the wetting behavior of a crystal near a wall and many other interfacial phenomena. However a direct determination of the free-energy is not possible in experiments and indirectly the available estimates are unreliable. In this talk I present a computational method to determine this quantity from molecular simulations and obtain conditions under which a crystal partially wets a wall an information which is essential to investigate heterogeneous nucleation. In the second part of my talk I use the simulation technique to compute the excess free energy of a supercooled liquid in contact with amorphous walls having the same structure as the liquid. Such systems are studied to validate theories pertaining to a bulk supercooled liquid in the context of the glass transition problem. Our results indicate that one has to be careful while interpreting the interfacial behavior as being representative of the bulk liquid.Short biography: Dr. Ronald Benjamin is currently a Postdoctoral Fellow at the soft Matter Institute in Heinrich-Heine University. Previously he had post doctoral stints at Institute of Material Physics in Space DLR (German Aerospace Center) Cologne and Department of Chemical and Biological Engineering University of Colorado at Boulder. Dr. Benjamin’s basic education has been in Physics all along and he did his PhD in Physics from University of Alabama at Birmingham. Dr. Benjamin’s research interest is in theoretical and computational condensed matter physics where he looks at various problems in soft matter physics and that in non-equilibrium statistical mechanics and thermodynamics.
(Attendance compulsory for CL702 students)