Nov
1
4:00 pm16:00

MRSEC Seminar: Metal-Organic Magnets Incorporating Redox-Active Semiquinoid Ligands: From Molecules to Materials

  • COLUMBIA UNIVERSITY

Prof. David T. Harris
Department of Chemistry
Northwestern University

Date: Tuesday, November 1, 2016
Time: 4:00 pm
Place: 750 CEPSR
Host: Xavier Roy

 

ABSTRACT

Molecule-based metal-organic magnets offer several key advantages over their inorganic counterparts, such as chemical control and tunability of structure and function, solution-based synthesis and processability, and low density. These compounds may find use in applications including spin-based information storage and processing, the development of lightweight permanent magnets, and the magnetic separation of gases. All of these applications would benefit from a higher operational temperature, which is directly correlated to the strength of magnetic interactions within the compound. This presentation will describe our efforts to synthesize metal semiquinoid molecules and extended solids that feature strong magnetic exchange coupling between metal and ligand radicals. More specifically, it will present the synthesis and properties of new radical-bridged compounds comprising dinuclear molecular complexes, one-dimensional chain compounds, and two-dimensional layered materials. In addition to magnetic properties, electronic conductivity and optical properties of these compounds will be presented. 

 

Oct
18
4:00 pm16:00

MRSEC Seminar: Excitons, Disorder, and Nonequilibrium Transport in Semiconductor Nanomaterials

  • COLUMBIA UNIVERSITY

Prof. William A. Tisdale
Department of Chemical Engineering
Massachusetts Institute of Technology

Date: Tuesday, October 18, 2016
Time: 4:00 pm
Place: 750 CEPSR
Host: Xiaoyang Zhu
 

ABSTRACT

In nanostructured materials, the short length and time scales over which energy moves can present transport behavior that deviates from classical constitutive laws. Using a combination of ultrafast spectroscopy, time-resolved optical microscopy, and kinetic Monte Carlo simulation, I will show how these effects manifest in assemblies of colloidal quantum dots (QD) and atomically thin 2D semiconductors, which are promising components of next-generation photovoltaic and lighting technologies. In particular, we will explore the effect of structural and energetic disorder, the role of nanocrystal surface chemistry, and the self-organization of these nanomaterials into ordered superstructures.

BIOGRAPHY

Will Tisdale joined the Department of Chemical Engineering at MIT in 2012, where he is the Charles & Hilda Roddey Career Development Assistant Professor. His research program is focused on the development of nanoscale semiconductor materials for use in next-generation energy technologies. Will earned his B.S. in Chemical Engineering from the University of Delaware in 2005, his Ph.D. in Chemical Engineering from the University of Minnesota in 2010, and was a postdoc in the Research Laboratory of Electronics at MIT before joining the faculty in 2012. He is a recipient of the Presidential Early Career Award for Scientists and Engineers (PECASE), the DOE Early Career Award, the NSF CAREER Award, an Alfred P. Sloan Fellowship, and MIT’s Everett Moore Baker Award for Excellence in Undergraduate Teaching.


Web: http://web.mit.edu/tisdalelab