Spring 2019                                              

Friday, Jan 11 

Prof. Jeremy Johnson from the Dept. of Chemistry and BIochemistry at Brigham Young University, will present "Distinguishing Nonlinear Terahertz Excitation Pathways with 2-Dimensional Spectroscopy." Byker Auditorium 3:10 pm. Prof. Erik Grumstrup host.

Abstract: High-field terahertz (THz) spectroscopy is enabling the ultrafast study and control of matter in new and exciting ways. However, when intense electromagnetic pulses are used in any kind of pump-probe spectroscopy, several nonlinear excitation pathways can result, leading to scenarios that required the development of multi-dimensional spectroscopies to illuminate the observed dynamics. I’ll describe a clear example where 2-dimensional (2D) THz vibrational spectroscopy is needed to distinguish between nonlinear-excitation pathways in crystalline CdWO4.

Friday, Jan 18

Dr. David Zigler Assistant Professor from the Dept. of Chemistry and Biochemistry California Polytechnic State University-San Luis Obispo.  will present "Electronic State Tuning through Metal-Ligand Covalency: First Row Transition Metals are Worth Exciting!"

Byker Auditorium at 3:10 pm. Professor Erik Grumstrup is the host.

Abstract: First row transition metal (TM) complexes are attractive as photosensitizers. Often as highly-colored as complexes formed from 2nd or 3rd row TMs, metals from the first row are orders of magnitude more abundant. The challenge in using 1st row TM complexes is that they have low-lying metal-centered ligand field states (MC) that provide a pathway for rapid relaxation to the ground state. Recent results show that complexes with highly covalent metal-ligand bonds have destabilized MC states and long-lived charge transfer excited states (CT). Our group studies ligand substituent effects on metal complexes formed with dithiocarboxylic acid derivatives using a mixture of experimental and computational methods. This talk will discuss ligand design strategies and show a set of tris(dithiocarboxylate)cobalt(III) complexes with destabilized MC states and an unusual low-lying metal-to-ligand charge transfer (MLCT) state.

Thursday, Jan 24

Dr. Keith Hollis from the Dept. of Chemistry at Mississippi State University will present "Designing, Developing and Applying Molecules to Solve Tomorrow’s Problems: CCC-NHC Pincer Complexes: Early and Late Transition Metal Complexes – Synthesis & Applications."   Byker Auditorium at 3:10 pm

Abstract: The Hollis Group designs and develops next-generation organometallic ligands and complexes (CCC-NHC pincers) for many applications, which often requires the development of new synthetic methodologies. Access to new molecules and materials is required to solve many of the technological challenges facing society, such as improving energy-efficiency, direct conversion of solar energy to useful forms, and more cost-effective access to medicines. These goals are reached by developing efficient, scalable syntheses of molecules with interesting properties.

Friday, Jan 25 -

Dr. David Lee, Washington State University.  Prof. Tim Minton host. 

Friday, Feb 1-

Prof. Anje Kunze

Friday, Feb 8

Prof. Scott Warren from UNC, Chapel Hill will present "2D Heterostructures for Energy Storage and Electronics: Exploring the Limits of Weak and Strong Interlayer Interactions." 

Abstract: The ability to alter distances between atoms is among the most important tools in materials design.  Despite this importance, controlling the interlayer distance in stacks of 2D materials remains a challenge.  This talk will present two strategies for controlling this distance, thereby giving rise to several fascinating new classes of materials for electronics and energy storage.

 In the first strategy, we self-assemble a monolayer of organic molecules between monolayers of a 2D semiconductor such as MoS2 or phosphorene.  The resulting 3D materials are crystalline and have an increased interlayer distance, which gives rise to fascinating and unusual electronic properties.  We demonstrate a 3D hybrid made from monolayer MoS2 and organic molecules that retains the desirable properties of monolayer MoS2, such as strong photoluminescence.  Even more surprising is that these materials are relatively conductive—thereby allowing the desirable properties of 2D materials to be harnessed in a 3D format that is suitable for electronic devices.

The second strategy introduces a new pathway to reduce interlayer distance.  We utilize “2D electrenes,” a new 2D material with an electrical conductivity that rivals silver (JACS 138, 16089, 2016).  2D electrenes have radically different electronic structures: they have planes of electrons that are physically separated from planes of cations.   Using DFT calculations and preliminary experiments, we show that electrenes act as electron donors to 2D metals, semiconductors, and insulators.   These materials are the 2D analogs of donor-acceptor systems and have interlayer distances that approach those of covalent or ionic materials.  I will describe these structures and their fascinating properties, as well as their role in battery electrodes.

Byker Auditorium at 3:10 pm. Prof. Nicholas Stadie host.

Friday, Feb 15

Dr. Bryan Eichhorn from the University of Maryland, Dept of Chemistry and Biochemistry.  Prof. Rob Walker host

Friday, March 1

Dr. Mitch Smith (Michigan State). Prof. Joan Broderick host.

Friday, March 8

Dr. Alex Guo (Carnegie Mellon University). Prof. Jen DuBois host.

Friday, March 15 

Dr. Orion Berryman (UM)  Prof. Mary Cloninger host. 

Tuesday, March 26

Ph.D Defense in Chemistry- Eric Smoll

Friday, March 29

Dr. Elliot Hulley (University of Wyoming) Prof. Michael Mock host

Friday, April 5 

Prof. Timothy Warren (Georgetown University).  Prof. Michael Mock host

Friday, April 12

Dr. John Tunge (Kansas). Prof. Matt Cook host

Friday, April 19- University Holiday

Monday, April 22

Graduate Student Seminar -Stella Impano

Friday, April 26

Dr. Joan Valentine (UCLA).  Graduate students host. 

Friday, May 3

Dr. Joe Topczewski (University of Minnesota). Prof. Matt Cook host.