Binghamton University
Department of Physics, Applied Physics and Astronomy
Department of Materials Science and Engineering
PHYSICS AND MATERIALS COLLOQUIUM
Dr. Jerome Delhommelle
Assistant Professor, Department of Chemical Engineering
Adjunct Assistant Professor, Department of Chemistry and Biochemistry
University of South Carolina
Columbia, South Carolina
Title: "Cross-nucleation and polymorph selection: unravelling the competition between kinetics
and thermodynamics"
Abstract:
Controlling polymorphism, that is, in which structure atoms (or molecules) crystallize, still remains an unsolved
problem. Since polymorphs generally have different physical properties, understanding this phenomenon is
crucial for many applications. In this work, we use molecular dynamics simulations to study the early stages of
the crystallization process in supercooled liquids of spherical particles. We present a few results obtained
recently in our group:
- we propose the first molecular mechanism for the experimental observation of cross-nucleation between
polymorphs [1],
- we demonstrate how cross-nucleation can be controlled and, more generally, how the control of polymorphism
can be achieved for a simple Lennard-Jones fluid [2],
- we provide some insight into the molecular mechanisms underlying polymorph selection in charge-stabilized
colloidal suspensions [3],
- we elucidate the pathway to crystallization of Aluminum and analyze the differences with the crystallization
mechanism of a simple fluid [4],
- we provide numerical evidence for a structural evolution of -N2 critical nuclei into -N2 crystallites [5].
[1] C. Desgranges and J. Delhommelle, J. Am. Chem. Soc. 128, 10368 (2006).
[2] C. Desgranges and J. Delhommelle, Phys. Rev. Lett. 98, 235502 (2007).
[3] C. Desgranges and J. Delhommelle, J. Am. Chem. Soc. 128 , 15104 (2006).
[4] C. Desgranges and J. Delhommelle, J. Am. Chem. Soc. 129, 7012 (2007).
[5] J.-M. Leyssale, J. Delhommelle and C. Millot, J. Am. Chem. Soc. 126, 12286 (2004).
Monday, September 24, 2007
S2 Bldg. Room 243
PRESENTATION 2:30 PM– 3:30PM
ALL WELCOME – COFFEE AND REFRESHMENTS AT 2:20PM