DWIS Seminar: Professor Sarah Stoll, Georgetown University
Credit: Georgetown University
About the Seminar
Synthesis of Two-Dimensional Lanthanide Chalcogenides
This talk will focus on three related classes of magnetic lanthanide (Ln) chalcogenide (Q = S, Se, Te) nanomaterials that exhibit a range of anisotropy in structure, bonding and magnetic order. The three classes include: 1) monochalcogenides EuQ (Q = S, Se, Te) with ionic cubic structures (Heisenberg magnets), 2) dichalcogenides (LnSe2, LnTe2, EuSe2, EuTe2) with ionic layered structures (Ising magnets), 3. tritellurides (LnTe3) van der Waals layered materials (XY magnets). Our goal is to develop synthetic methods to control phase, size and shape and to control the nucleation and growth of the nanomaterials to form two-dimensional nanosheets. Here two-dimensions are defined as nanosheets with lateral dimensions >200nm, and thicknesses < 20nm. The scientific questions we aim to address include: How can anisotropic crystal growth be controlled in lanthanide chalcogenides, especially as the bonding transitions from isotropic (monochalcogenides) to highly anisotropic (tritellurides)? When reduced in dimension to few layer nanosheets, what happens to the properties, particularly long-range magnetic order? .
About the Speaker
Sarah Stoll graduated from Smith College in 1988, and U. C. Berkeley in 1993. Post-graduate work included a one year as a visiting professor at Oberlin College and a post-doctoral fellowship with Andrew Barron at both Harvard and Rice Universities. After receiving tenure at Oberlin College, she moved to Georgetown University in 2002. She has been a visiting scientist at Helsinki University of Technology (on a Fulbright), Université Pierre et Marie Curie, the National Institute for Standards and Technology, and Oxford University. She has been a program officer at the National Science Foundation, earned the Dean’s Teaching Award, and was the Sonneborn Chair for interdisciplinary collaborations. In addition to interests in inorganic chemistry, she also teaches environmental chemistry in the Environment, Metrology and Policy Program at Georgetown University.