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04/30/2015

Nine students receive Doctoral Dissertation Fellowships

Nine of the Department of Chemistry's top doctorate students have received 2015-16 Doctoral Dissertation Fellowship program awards. Recipients include Joshua Borycz who is advised by Professor Laura Gagliardi; Laura Clouston who is advised by Professor Connie Lu; Ian Gunsolus who is advised by Professor Christy Haynes; Rebecca Mackenzie who is advised by Professor Kenneth Leopold; Moshen Mahmoodi who is advised by Mark Distefano; Deborah Schneiderman who is advised by Professor Marc Hillmyer; Jennifer Strehlau who is advised by Professors Lee Penn and Bill Arnold; Evan Weitz who is advised by Professor Valerie Pierre; and Haoyu Yu who is advised by Professor Donald Truhlar.

The Doctoral Dissertation Fellowship program gives the university's most accomplished doctorate candidates an opportunity to devote full-time efforts to outstanding research projects by providing time to finalize and write a dissertation during the fellowship year. Awardees receive an academic year stipend of $23,000 and tuition. They participate in a monthly seminar series, present their research at an annual poster session, and receive travel grants to present their work at national or international conferences.

Joshua Borycz is entering his 5th year of graduate school under the supervision of Professor Laura Gagliardi. Her research focuses on computational characterizations of metal-organic frameworks (MOFs). These characterizations involves the use of quantum mechanical methods to compute the magnetic, catalytic, and physical properties of MOFs. Joshua specializes in using periodic density functional theory (DFT) for these calculations. He has computed the magnetic properties of Fe-MOF-74 using cluster level wavefunction theory (WFT) and periodic DFT. It was discovered that the magnetic ordering within this MOF changes when certain guests are introduced in the pores, which is a property that may eventually be used for molecular sensing. Currently, Joshua is working on using atomic layer deposition of metal clusters within NU-1000 for eventual use a catalyst for the reaction of methane to methanol. Also, his work involves using quantum mechanics to parameterize force fields for macroscopic calculations.So far, he has computed force fields for CO2 adsorption within the MOF-74 and IRMOF series with multiple metal centers. This work is important because it allows us to predict the types of metal and MOF topologies are likely to favor interaction with CO2.

Laura Clouston is entering her fifth year of graduate study under the supervision of Professor Connie Lu. Laura’s research interests are focused on the synthesis and study of heterobimetallic complexes featuring multiple bonds between metals. Multiple bonds between two different first row transition metals are relatively rare, so the spectroscopic study of these bonds in connection with theoretical calculations provides a better understanding of this new class of bonds. Recently, Laura has moved toward studying dinitrogen activation with metal-cobalt bimetallics. She has been able to swap out the supporting metal in these complexes to study how different metals can tune the reactive cobalt site.

Ian Gunsolus is entering his fifth year of graduate study under the supervision of Professor Christy Haynes. His research encompasses engineered nanomaterial interactions with biological systems and their transformations in the environment. Bacteria are used as model organisms throughout his research to understand the potential consequences of engineered nanomaterial release into the environment. Ian studies the fundamental mechanisms of interaction between bacterial cell membranes and engineered nanomaterials, with the goal of informing the design of sustainable nanomaterials. In this context, he has also characterized the toxicity of emergent, industrially relevant classes of nanomaterials, such as those used in next-generation lithium-ion batteries.

Rebecca "Becca" Mackenzie is entering her fifth year of graduate study under the supervision of Professor Ken Leopold. Becca studies molecular complexes using high resolution microwave spectroscopy. Employing both conventional cavity-type and the newer chirped-pulse Fourier transform microwave techniques, she has studied a wide variety of systems and has provided deep and careful analyses as to their broader chemical and physical significance. Her most important work has been the observation and characterization of formic sulfuric anhydride, which she has identified as a potential player in atmospheric aerosol formation. Her other work has involved diverse topics such as double proton transfer, large amplitude vibrational dynamics, and the measurement and interpretation of molecular electric field gradients in weakly bound systems.

Mohammad "Mohsen" Mahmoodi is entering his 6th year of graduate study under the tutelage of Professor Mark Distefano. His research is focused on development of light-activatable biomolecules and peptides for studying cellular processes or as light-activatable therapeutics. He is currently developed UV and IR sensitive cysteine containing peptides for studying thiol mediated biological pathways. These peptides can penetrate inside cell via crossing the plasma membrane. Upon irradiation they will be activated, processed by enzymes and migrate to different organelles which allows us to study kinetics of related cellular processes. In collaboration with other groups, Mohsen is also trying to apply similar technique to develop light-sensitive biomaterials such as 3D patterned hydrogels, which can serve as a mimic for extracellular matrix. These novel materials are key for elucidating cellular activities.

Deborah “Debbie” Schneiderman is entering her fifth year of graduate study under the supervision of Professor Marc Hillmyer. Her research focuses on the synthesis of novel degradable polymers from biorenewable monomers.  Specifically, she works with polyester  block  polymers comprised of  soft rubbery segments covalently linked to  hard glassy or semicrystalline  segments. She is studying how changes to the structure of the soft domain change the material's thermal characteristics, degradation rate, and mechanical properties. She also investigates the influence of chemical  structure on the  kinetic and thermodynamic polymerizability of lactone monomers. 

Jennifer “Jen” Strehlau is entering her fifth year of graduate study. She is co-advised by Professor Lee Penn and Professor Bill Arnold from Civil, Environmental, and Geo- Engineering. Her thesis work studies iron oxide reactivity toward groundwater contaminants in the natural environment, which is a promising remediation method for solving today’s rising water crisis. Her research explores the effect of common environmental variables, such as pH, ionic strength, and mineral composition, on the accessible reactive surface area and resultant reactivity of iron oxide nanoparticles in aquatic systems. Jen’s work is highly interdisciplinary, employing materials techniques such as X-ray diffraction, magnetic characterization, and cryogenic microscopy in tandem with kinetic studies of redox reactions. She demonstrates, at a fundamental level, how these variables affect the reactivity of iron oxides and efficiency of groundwater remediation, which will enable a better transition from laboratory research to field application.

Evan Weitz is entering his fifth year of graduate study under the supervision of Professor Valerie Pierre. Evan’s research interests consist of the development of small metal-based sensors for imaging biological processes. Evan is currently focused on the development of fluorine-based, responsive MRI contrast agents. These small metal-based complexes have the capability to improve the prognoses of many diseases, the causes of which could previously only be detected antemortem. In addition to proof-of-principle studies, Evan also works with collaborators in different fields to improve MRI acquisition parameters and to examine the biocompatibility of these contrast agents, their risk of side effects, clearance times, and their biodistribution in vivo.

Haoyu Yu is entering his fifth year of graduate study under the supervision of Professor Donald Truhlar. His research focuses on density functional development (DFT). DFT is a computational method that is used to study the electronic structure of atoms, molecules, and solids. There are many problems that are very hard to solve by DFT, for example, transition metal chemistry and van der Waals interactions. His goal is to develop a series of density functionals that improves significantly on previous functionals for these problems, while retaining the high accuracy of previous functionals for the kinds of cases where they gave good results. A second objective is to make the new functionals smoother than previous ones to make the numerical methods more stable. Currently, two density functionals have been developed, called GAM and M15-L, which are able to achieve high accuracy at low computational cost. A long-term goal is to develop a universal functional that gives high accuracy for all the properties and processes in chemistry and physics.