Chemistry Colloquium Program
Day: Friday
Time: 3:30 PM CDT
Location: A101 Annex Auditorium, Life Sciences Building
Unless otherwise noted, seminars will be held on Fridays in the A101 Annex Auditorium at 3:30 PM. Check the individual notices posted on bulletin boards or your e-mail box for confirmation of times and locations.
*Denotes Gameday Weekend
Fall 2024 Schedule
Jason P. LeJeune, Ph.D.
LSU Environmental Health & Safety
Safety Seminar
Host: John A. Pojman
Matthew Chambers, Ph.D.
Department of Chemistry
Louisiana State University
"Developing Molecular Catalysts for Sustainable and Energy-Efficient Petrochemical Processes"
The foundation of chemical industry continues to have an over-reliance on processes developed in the early 1900’s that leverage high temperatures and high pressures to drive a given reaction of need. Today, such strategies consume substantial energy while generating copious amounts of hazardous waste. While these industries produce critical commodities to support societies' survival and growth, there is a need for major scientific innovation to allow for chemical industry to continue to thrive in a more sustainable and energy-efficient manner. This presentation will describe two parallel approaches to modernizing catalysis to meet this challenge. The first approach will present a new class of carbonylation precatalysts based on mid-valent metal centers capable of supported catalysis at relatively mild temperatures and pressures. The characterization, activity, stability, and nature of the catalytic state will be discussed. The second approach will present the development of novel reaction pathways suitable for the direct formation of C–C bonds from unactivated hydrocarbon sources. The ability of metal oxo complexes to activate C–H bonds is combined with photochemical activation to generate a unique electronic configuration suitable to mediate the bond activation while allowing a diverse array of follow-up reactivity and product selectivity. Mechanistic insights, the nature of the excited state, the development of photocatalytic conditions, and strategies to control product selectivity will be presented.
Host: Justin Ragains
Manuel Hegelich, Ph.D.
Department of Physics
The University of Texas at Austin
"Miles to Meters – Can Laser-Driven Accelerators Supplant Large-Scale Facilities?"
Recent years have seen significant advances in laser-driven accelerator systems in terms of reliability and reproducibility as well as in terms of bunch energy, charge and emittance. At UT Austin we have investigated and developed the underlying scientific principles. At TAU Systems, Inc., we aim to integrate those advances into a single system, allowing a transition from the laboratory to the market. We will present recent results on laser-driven particle acceleration and our current plans to utilize such laser systems to generate high-energy electron beams as drivers for table-top synchrotron-like x-ray sources, compact gamma-ray and neutron sources and even compact EUV/X free-electron laser systems. These systems can drive applications in semiconductor R&D and metrology, medical and material science applications as well as fundamental and applied nuclear physics, chemistry, biology and pharmacology. We will show recent advances in wakefield target technology, demonstrating for the first time > 10 GeV electrons from a laser wakefield accelerator and how this enables laser-driven XFELs, as well as recent progress on smaller, compact high repetition rate systems and a laser-based light source service center.
Joint Seminar: Chemistry with Physics & Astronomy
Host: Gerald J. Schneider
Revati Kumar, Ph.D.
Department of Chemistry
Lousiana State University
"Liquid electrolytes: From Aqueous Solid-Liquid Interfaces to Ion Solvation in Non-Aqueous Systems"
The research focus of my group is to investigate the effect of solvation environment on charge transport, structure and dynamics of both aqueous and non-aqueous electrolytes using molecular simulations. An important aspect of our research is understanding the effect of secondary/non-covalent interactions on the properties of electrolytes both in the bulk and at the interface using molecular simulations. The interface is essentially a region wherein the symmetry of the bulk environment is broken and thus can include a wide range of systems from the surface of an electrode in contact with an electrolyte to an aggregate/micelle in contact with a solution. I will present two systems that my group is working on. The first part of my talk will focus on graphene oxide (GO)-aqueous solution interfaces. Graphene oxides (GOs) are nanoporous sheets of graphene with oxygen bearing defects. This interface is critical for many exciting GO-based separation technologies such as water purification and proton exchange membranes. Our group has used ab initio molecular dynamics simulations coupled with neural network force-field simulations to investigate the interfacial aqueous structure and the intrinsic reactivity of these aqueous interfaces. Comparisons between conventional force-fields and first principles ab initio molecular simulations will be discussed and the results partially validated on recent vibrational sum frequency generation spectroscopy data. Furthermore, the effect of oxidation level of the sheet, from fully oxidized sheet to the unoxidized graphene-water interfaces, on reactivity and interfacial ordering will be presented. The effect of solvent polarity will be presented based on results obtained by changing the solvent to methanol. The classical force-fields that best reproduce the ab initio MD simulation interfacial solvent data was used to study the adsorption of organic aromatic molecules onto graphene oxide. The effect of the oxidation level of the graphene oxide sheet as well as the presence of two different halide salts, sodium chloride and sodium iodide, were examined and the results will be presented. The second part of my talk will focus on glyme based electrolytes that unlike their aqueous analogues, have received comparatively little attention from a fundamental perspective. The structure of these linear chain ethers is reminiscent of crown ethers, hence they are excellent cation chelators. The efficient cation solvation of glymes in turn impacts counterion reactivity and transport. Solutions of metal salt in glymes have a wide range of applications, including but not limited to organic synthesis, biocatalysis, electrochemistry, and energy storage technologies. The focus of the Kumar group is to investigate the role of ion solvation on the chemical properties of glyme based sodium salt electrolytes that are relevant to energy storage applications. Given the inadequacies of "off the shelf" effective pair potential in describing these electrolytes, the development of inexpensive force-fields to study these systems is essential. The Kumar group uses data from ab initio quantum simulations in conjunction with experiments in the condensed phase to develop and test new empirical atomistic models of sodium triflate in diglyme. The details of the force-field development as well as the transferability of these models to glymes of different chain lengths as well as different anions with similar chemical motifs as triflate will be discussed. The results from the simulations on the solvation structure, charge transport and aggregation as a function of glyme chain length and anion identity as well as in the presence of electrode interfaces will be presented.
Host: Bin Chen
Patrick Mensah, Ph.D.
Associate Dean for Research and Graduate Studies
Professor of Mechanical Engineering
"CREST Center for Next Generation Multifunctional Composites Research at Southern University"
Southern University and A&M College (SU) in Baton Rouge, LA, in collaboration with Louisiana State University (LSU), established Phase II CREST Center for Next Generation Multifunctional Composites with NSF funding. CREST Center projects involves promoting advancements in multifunctional smart composites and related technology development, nanocomposites, novel microstructure design, and multiscale porous polymer composites, including materials synthesis and characterization, computational modeling and simulation, and additive manufacturing and applications.
Host: John A. Pojman
Haitao Liu, Ph.D.
"Intrinsic Surface Properties of Graphitic Carbon Materials"
Our research shows that the perceived hydrophobicity of graphitic carbons arises from the adsorption of airborne hydrocarbons on their surfaces. Additionally, this form of contamination significantly influences both the heterogeneous electron transfer rate constant and the double-layer capacitance of carbon electrodes. These findings underscore the critical role of surface cleanliness in characterizing and utilizing carbon materials in ambient conditions.
Hosts: Graça Vicente, Slava Baranets
Rafael Cueto, Ph.D.
Director, LSU Shared Laboratory for Macro and Bio-Macromolecular Research
"Opportunities at SLMBR and Crystallography"
The LSU Shared Laboratory for Macro and Bio-Macromolecular Research (SLMBR) provides advanced equipment for characterization of macromolecules, supramolecular assemblies, colloids, complex fluids, and related materials. This facility was previously known as the Polymer analysis Laboratory (PAL)
The following techniques will be discussed:
- Thermal analysis: Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis
(TGA), Dynamic Mechanical Analysis (DMA), and Rheology.
Gel Permeation - Chromatography: Multi Angle Light Scattering GPC (GPC-MALS) and Conventional Calibration GPC.
- Dynamic Light Scattering and Zeta Potential.
LSU X-ray Crystallography Facility - A brief outline of structure determination by single-crystal X-ray diffraction will be given. Our diffractometers and software will be described, with emphasis on the advantages and drawbacks of each of our three radiation sources, Ag, Cu and Mo.
Host: Daniel Kuroda
Fall Break - No Colloquium
Ognjen Miljanic, Ph.D.
Department of Chemistry
University of Houston
"Cyclobenzoins: Uses in Energy and Environmental Studies"
Cyclobenzoins are organic macrocycles prepared in a single air- and moisture-tolerant step by the benzoin condensation of aromatic dialdehydes. Despite their simple structure, they are characterized by a range of interesting properties: electrochemical activity, porosity in the solid state, and well-developed derivatization chemistry. We have explored these properties in the context of energy-related uses. Cyclobenzil hydrazones have been shown to capture iodine from vapors, solutions, and interfaces, while cyclobenzils themselves have been employed as components of organic electrode materials for lithium-ion batteries. Meanwhile, acetylated cyclotetrabenzoin has been shown as a supramolecular host for linear pi-electron rich guests, including terminal alkynes and CO2. Together with the Zaworotko group at the University of Limerick in Ireland, we have also shown that cyclotetrabenzoin acts as a superior platform for the separation of C3 hydrocarbons, with the greatest affinity for propyne. Derivatization of cyclobenzoins into other macrocyclic species will also be discussed.
Host: Victor Garcia-Lopez
"Introduction to the State-of-the-Art Instrumentation and Capabilities of LSU Shared Instrumentation Facility"
Managed under Office of Research and Economic Development (ORED) at LSU, the Shared Instrumentation Facility (SIF) offers instrumentation which supports materials characterization including scanning electron microscopy (SEM), transmission electron microscopy (TEM), Bright, Fluorescent or Confocal Light Microscopy, Focus Ion Beam (FIB) for surface morphology, micro-nano or crystal structure analysis and X-ray Diffractometry (XRD), X-ray Photoelectron Spectroscopy (XPS), X-ray Energy Dispersive Spectroscopy (EDS) etc. for chemistry analysis for many scientific and engineering disciplines. It operates as a cost-recovery center providing not only instrumentation but also specimen preparation and processing. The facility is staffed by on-site specialists to assist academic and non-academic (e.g., industry) users with their data acquisition and training needs. SIF is open to all LSU faculty, staff and students as well as employees of other academic and industrial units.
Host: Gerald Schneider
Fereshteh Emami, Ph.D.
Southeastern Louisiana University
"Assessment of Chemical Contaminants in Lake Maurepas"
Lake Maurepas in southeastern Louisiana (USA) is a vital aquatic ecosystem with significant ecological, recreational, and economic value. Recently, concerns have arisen regarding the deterioration of aquatic and water quality within the lake, largely attributed to the industrial activities. Our study aims to investigate the chemical contaminants and the quality of water, sediment, and aquatic samples collected from various locations and depths of the lake. The primary objectives of this study are to assess the current state of organic pollutants, nutrients and heavy metal concentrations, and to identify the monthly concentration trends and spatial contaminants distribution patterns throughout the lake. The behavior of these chemicals was analyzed and forecasted using parametric and non-parametric statistical analyses, as well as machine learning-based modeling. The findings of this study contribute to the understanding of aquatic ecosystems and provide insights into the effects of pollution on the ecosystem.
Host: John A. Pojman
Elisabeth Fatila, Ph.D.
Louisiana Tech University
"Mechanochemical synthesis for coordination chemistry: a solution to synthetic issues with the larger lanthanides?"
The importance of lanthanides to new and emerging technologies cannot be overstated. Coordination chemistry is key to developing compounds that harness the magnetic and optical properties of the lanthanides. While lanthanides are often treated interchangeably because of their similar chemical properties, the decrease in ionic radius across the series can have substantial consequences to their coordination chemistry. The larger, more charge diffuse early lanthanides tend to have higher coordination numbers for the same ligand set with reduced stability constants. With the greater synthetic flexibility of the larger lanthanides, there can be challenges with obtaining targeted products reproducibly. In addition, the dynamic and labile nature of Ln3+ cations means that solvents can have a detrimental impact on yield and purity.
We look critically at the role mechanochemistry plays in optimizing yields and reducing side products. Both manual grinding and automated ball milling were used for mechanochemical reactions. While mechanochemistry can remove the impact of solvent, other strategies were used alongside mechanochemical synthesis. Additional synthetic strategies including tuning the steric features of ligands were found to play a role in stabilizing complexes of the early lanthanides and affording greater reaction reproducibility.
Future work includes using mechanochemistry and our ligand strategy for the coordination chemistry of larger and more charge diffuse cations.
Vicky Colvin, Ph.D.
Host: John A. Pojman
Thanksgiving - No Colloquium
Student Awards Ceremony
Students will be awarded the:
Mary Jo Pribble Inorganic Chemistry Award
Timothy S. Evenson Macromolecular Chemistry Award
H. Dupont Durst Organic Chemistry Award
Neil Kestner Physical Chemistry Award
Dow Chemical Macromolecular Award
Kiran Allam International Award
James G. Traynham Teaching and Research Award
Hosts: David Spivak, Kandace Hurst
Student Award Presentations
Host: David Spivak
SPRING 2025 Schedule
Jason P. LeJeune, Ph.D.
LSU Environmental Health & Safety
Safety Seminar
Host: John A. Pojman
Vicente A. Talanquer, Ph.D.
Host: Zakiya S Wilson-Kennedy
Martin Head-Gordon, Ph.D.
Host: Kenneth Lopata
P. Shiv Halasyamani, Ph.D.
Host: Slava Baranets
Gina Frey, Ph.D.
Host: Zakiya S Wilson-Kennedy
Joseph Schlenoff, Ph.D.
Host: Amy Xu
Erin McCauley, Ph.D.
Hosts: Jose M. Garfias, Fatima Rivas
Scott Snyder, Ph.D.
Host: Fatima Rivas
Mihaela C. Stefan, Ph.D.
Host: David Spivak
"Opportunities Created by the Mass Spectrometry and Nuclear Magnetic Resonance Facilities at LSU Chemistry and Beyond"
The LSU College of Science Mass Spectrometry Facility (MSF) is a cost center located on the main campus in Baton Rouge, LA. The facility currently houses six mass spectrometers that are available for organic, inorganic and biological mass spectrometric applications. The facility is directed by Dr. Fabrizio Donnarumma, Ph.D., and employs Dr. Isabel Vitorino Maia as research associate. The team is responsible for operating the instrumentation, maintenance, sample preparation and data analysis. In addition, the MSF provides assistance in experiment design, teaching activities that include mass spectrometry as well as grant writing and design support.
The LSU NMR Facility has six instruments with magnetic fields of 400, 500, and 700 MHz, offering both solution and solid-state capabilities. These instruments support routine 1H, 13C, and 31P 1D and 2D experiments, useful for research in chemistry, engineering, biology, and other fields. For more complex needs, the Bruker pulse sequence library and advanced NMR hardware provide enhanced capabilities. We'll explore some of the non-routine experiments possible with our instruments and the research questions they can help address.
Host: Robert Cook
Spring Break - No Colloquium
Good Friday - No Colloquium
Kelly Ayers
"Introduction to Topics in Crime Scene Investigation"
Hosts: Gerald Schneider, Julia Carroll representing the Student Affiliates of the American Chemical Society (SAACS)
Yan Xia, Ph.D.
Joint Seminar: Chemistry and Chemical Engineering
Hosts: Anthony Engler, Donghui Zhang