Tobin Jay Marks - US grants

Unusual structural, electronic, thermodynamic, and reactivity characteristics of the actinide and related elements will be determined. Phenomena to be investigated include metal-ligand bond enthalpies and reaction thermodynamics, metal-heteroelement bond chemistry, ancillary ligand effects and enantioselective transformations, the activation of hydrocarbon and related molecules, metal-metalloid and metal-metal bonds, as well as unusual oxidation states and ligands. The long range goal is to understand those structural and electronic factors which modulate chemical reactivity, and to capitalize on features which stimulate new or enhanced modes of chemical reactivity. %%% In this project in the Inorganic, Bioinorganic, and Organometallic Program of the Chemistry Division, Dr. Tobin J. Marks of Northwestern University will continue studies of the organometallic chemistry of actinide and related elements. The basic scientific goal is to understand the factors that determine chemical reactivity, a knowledge that may allow enhanced reactivity of certain catalyst systems. The results may also be of use in dealing with nuclear wastes and learning more about their effect on the environment.

Professor Mark A. Ratner is supported by a grant from the Chemistry Division and the Graduate Education and Research Division at NSF for a Graduate Traineeship Program emphasizing the chemical aspects of molecule-based electronics. A team of six Northwestern University chemistry faculty members with teaching and research expertise in this and related areas will be assembled to provide graduate training and mentoring as well as research program direction in this area. To ensure the program leads to a net expansion of training within the chemistry department, an aggressive recruitment plan emphasizing minority and female students will be devised. Once recruited, the trainees will take part in a rigorous program designed to provide: 1) courses pertinent to the central themes of molecule-based electronics; 2) exposure to and interaction with leading academic and industrial researchers from outside Northwestern University; 3) research training within the laboratories of Northwestern University faculty; and 4) experience in team-oriented, interdisciplinary problem solving via collaborative research interactions. %%% Molecule-based electronics is the use of molecular materials for electronic or photonic applications. The scope of this field ranges from well-defined and well-understood phenomena such as nonlinear optical response of a single crystal of an organic chromophore to the more tantalizing and conceptually more difficult areas involving optical computing and optical memory storage systems at the molecular level. This interdisciplinary field encompasses not only chemistry, but also physics, engineering and materials science. With the emergence of the first commercial molecular electronic technologies, the need for U.S. trained Ph.D. level scientists has become self-evident. Funding provided through this Graduate Research Traineeship award will help to provide scientists in this area of national need.

In this project, part of the joint ONR/NSF Program on Interfaces to Superconductors and supported by the Divisions of Chemistry, Materials Research, and Electrical and Communications Systems, Professors Chang and Marks of Northwestern University are studying the properties of interfacial growth regions between films of high-temperature superconducting (HTS) materials and insulating metal oxides. Atomic layer epitaxy (ALE) will be employed using a pulsed organometallic beam epitaxy system which is capable of growing metal oxide films with atomic layer precision but is also adaptable to large-scale low-temperature conformable metal oxide films growth as required in manufacturing. Superconductor/insulator heterostructures will be investigated under a variety of growth conditions and microstructures and interdiffusion properties will be evaluated by a variety of physical techniques, including various electron and atomic-force microscopies. Surface chemical processes will be directly monitored as a function of growth conditions during ALE. Improving the nature of interfaces in high-temperature superconducting materials and insulating metal oxides is a crucial barrier which must be surmounted before HTS materials can be successfully incorporated on a large scale into electronic device technologies. This study will provide the information needed to fabricate key structures for HTS-based electronics and an accurate evaluation of the potential of different growth techniques in this arena.

This award is made to Northwestern University in support of the collaborative research of Prof. R.P.H. Chang and Prof. Tobin Marks by the Advanced Materials Program in the Chemistry Division, The Solid-State Chemistry Program in the Division of Materials Science and the Physical Foundations of Enabling Technology Program in the Division of Electrical and Communication Systems. The focus of the research will be the growth of metal oxide superconductor/insulator thin film heterostructures using atomic layer epitaxy. Organometallic precursors will be designed and synthesized to provide contiguous self sealing pinhole-free films. Pulsed organometallic beam epitaxy will be used to fabricate cuprate superconducting oxide superlattices on insulator(SIS) or normal metal oxide(SNS) heterostructure junctions. under a variety of experimental conditions. Scanning electron microscopy, scanning tunneling microscopy, atomic force microscopy, ion scattering spectroscopy, x-ray diffraction and Auger spectroscopy will be used to characterize the films and interfaces. Collaborations with several companies to fabricate and characterize junction devices are in place. Multilayer high temperature superconductor-based heterostructure junction devices are of current interest for microwave circuitry. The precise control of superconducting thin film composition, morphology and epitaxy provided by this research will enhance the performance of such devices.

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Marks

Major Research Instrumentation funds will be used to acquire instrumentation for polymer analysis: a high temperature gel chromatograph (GPC) and a light scattering detector, equipped with an argon ion laser, for additional detection capability. The available GPCs at Northwestern University do not have the high temperature capability or the sensitivity needed for cutting edge research in polymers. This new equipment will be installed in the Analytical Services Laboratory of the Department of Chemistry at Northwestern University. The greatest number of users will come from the Department of Chemistry, but the Department of Chemical Engineering and the Department of Materials Science and Engineering will also have research projects making significant use of this instrumentation. The equipment will address the need of several research groups to characterize polymer samples in terms of their molecular weights, molecular weight distributions, and hydrodynamic volumes in solution. This research covers a broad range of topics including new catalysts for polymerization, self assembly of supramolecular aggregates, thermo-responsive polymers for DNA sequencing, polymer degradation mechanisms, interfacial adhesion of semicrystalline polymers, and polymer processing. In addition to the important research that will benefit from the new instrumentation, there is a strong educational component. The graduate students, postdoctoral fellows, and undergraduate students using the instrument for their research will receive substantial benefit from working with a state-of-the-art instrument. In addition, a further benefit will come from a formal educational component of the instrument being available for laboratory classes. The combination of research and education applications will allow the benefit of this equipment to be felt by an increased number of users.

Major Research Instrumentation program funds will be used to acquire a gel permeation chromatograph for use in polymer analysis. This instrument will be use in a variety of projects of researchers in several departments at Northwestern University. The instrument will have a large impact on the research training of students, postdoctoral to undergraduate, by allowing them hands-on experience on a state-of-the-art instrument.

This award in the Inorganic, Bioinorganic and Organometallic Chemistry program supports research by Dr. Tobin J. Marks at Northwestern University to investigate fundamental aspects of new catalytic transformations involving lanthanide and related early transition metals. The strengths of bonds being made and broken in organometallic/catalytic processes will be quantified. Reaction calorimetry will be used to quantify the strengths of metal-ligand multiple bonds, of metal-main group ligand single bonds, and to "anchor" the data on an absolute scale. This fundamental scientific information will then used to: elucidate bonding, rationalize known reaction patterns, and develop principles for the invention of new, useful catalytic processes. New catalytic mechanisms will be investigated pertaining to transformations in which element-H bonds are added to unsaturated carbon-carbon bonds (hydroelementation) to selectively create heteroatom- containing organic molecules. The primary focus is on selective C-N, C-P, C-B, and C-S bond-forming processes, studying a range of precursor structures (C=C, C=C=C, C=C-C=C), characterizing rates, selectivities, substituent effects, and comparing intramolecular vs. intermolecular processes.

Catalytic cascades in which controlled sequences of coupled bond-forming processes (e.g., C-N + C-C) take place at single and proximate metal centers will also be studied and refined as ultimate routes to useful fine chemicals and bio-active molecules, as well as to establish new catalytic principles. Organolanthanide-catalyzed polymerization processes will be investigated that involve single or closely poised multiple metal centers coupled to element-H/metal-C exchange processes or to hydroelementation processes that produce new types of polymer chains "end-capped" with a heteroatom (e.g., Si, Sn, B, Al). The properties of chiral complexes having various symmetry environments will be studied with respect to structure, stability, and efficacy in enantioselective variants of catalytic transformations. Unusual chelating ligand structures having sulfur and phosphorus donor atoms will also be studied. In addition, actinide complexes will be investigated to compare/contrast electronic structure effects on catalytic properties.

This project focuses on organometallic/catalytic/materials chemistry in order to effect, characterize, understand, and disseminate to the community, unusual and potentially useful new stoichiometric and catalytic reactivity principles applicable to making more efficient, atom- economical catalytic processes for the production of fuels, plastics, pharmaceuticals, and other economically important chemicals. Participation in this multifaceted/multidisciplinary project, including interactions with industrial scientists, will prepare graduate, undergraduate, and postdoctoral students, having diverse backgrounds, for productive careers in industry, government laboratories, and academe.

This award from the Instrumentation for Materials Research Program and the Solid-State Chemistry Program will help Northwestern University with the acquisition of a high-resolution magnetic-sector mass spectrometer with electron impact (EI) and liquid secondary ion mass spectrometry (LSIMS) ionization sources. This instrument will be used to characterize a wide range of materials science compounds such as mesoporous supramolecular molecules, porphyrazines, novel molecular species for electronic device structure, and other macrocyclic materials. As this research has moved toward larger and more complex species, the availability of in-house state-of- the-art mass spectrometry instrumentation has become essential for characterization of these molecules. The requested instrument will improve on the mass spectrometry capabilities for in-house molecular characterization in several ways: (1) the increased sensitivity for high-resolution mass spectrometry with either electron impact (EI) or LSIMS ionization is essential for determination of elemental composition of these species; (2) the increased mass range for mass spectrometry with LSIMS ionization will allow both low- and high-resolution characterization of the higher molecular weight species which will continue to increase in molecular weight as the research programs at NU progress; (3) air-sensitive materials may be characterized without fear of decomposition during transit to another laboratory.

This award from the Instrumentation for Materials Research Program and the Solid-State Chemistry Program will help Northwestern University (NU) with the acquisition of a high-resolution magnetic-sector mass spectrometer with electron impact and liquid secondary ion mass spectrometry ionization sources and with appropriate sample inlets for compounds with a wide range of volatility and purity. This instrument will be a significant benefit to molecular characterization in the materials research efforts in the Chemistry Department. Currently such characterization is done by sending samples to external laboratories. In-house characterization with the requested instrument will benefit both the research and the educational efforts at NU. The availability of the requested instrument for in-house analysis will increase significantly the exposure of graduate students to modern analytical techniques. In addition to gaining a more complete characterization of the materials that they have synthesized, students also will gain a deeper understanding of the techniques used for the analysis, the reason for choosing different ionization techniques, and the accurate interpretation of the mass spectra gathered from this analysis.

This joint award made to Northwestern University by the Advanced Materials Program in the Division of Chemistry (MPS) and the Electronic Materials Program in the Division of Materials Research (MPS) is to synthesize new macrocyclic nitrogenous polyketonato/polyketoiminato complexes as well as metal alkyls and dialkylamides with polar metal-carbon and metal-nitrogen linkages for use as precursors in conventional, pulsed organometallic beam epitaxy, and atomic layer epitaxy film growth processes. With this award, Professors Chang and Marks will study precursor molecular architecture-volatility-thermal stability-surface reactivity relationships leading to more effective precursors. Transparent thin films of conducting oxides will be grown from these precursors using precision-pulsed vapor deposition techniques, and these thin films would have potential applications in flat-panel display and photovoltaic devices. Lattice-matched cubic film systems with oxidative dopants will be studied for producing efficient p-type conductor films using vapor phase deposition onto self-assembled monolayer templates to create desired film microstructural, optical and electrical functionalities. This highly collaborative effort will bring together materials science and chemistry research groups with educational and research opportunities for graduate and postdoctoral students.

With this award, novel precursors with polar metal-carbon and metal-nitrogen linkages will be prepared for use in conventional and precision-pulsed vapor deposition processes to prepare transparent thin films of conducting oxides. These precursors are expected to possess optimum molecular architecture, volatility, thermal stability and surface reactivity for the deposition of transparent thin films of conducting oxides. Sub-micrometer and nanometer scale patterns of the oxide films by soft lithography and coherent growth of dislocation-free islands will also be prepared.

This IMR award provides Northwestern University with funds for the acquisition of a cluster of SMTP servers, having a 64-bit operating system, with a large memory subsystem and with Myrinet (medium speed) interconnects. This cluster will be used for computational chemistry and materials science research at Northwestern University, particularly applications in electronic structure, in computational electromagnetics, and in Monte Carlo and molecular dynamics calculations where large memory capabilities are essential. Distributed parallel applications will also be emphasized. The cluster will also be used in graduate and undergraduate courses in engineering and sciences, and in REU, REST, MRSEC and other initiatives which use software that require large memory capabilities.

This IMR award provides Northwestern University with funds for the acquisition of a cluster of computers that will be used for computational materials research in chemistry and engineering, and for related educational programs. The computers in this cluster will have specialized performance characteristics which make it possible to run programs that require an exceptionally large amount of computer memory, and which in addition allow for several computers to run in parallel on the same program. Research applications to be considered include the modeling of a wide range of properties of materials, including structures, energies, interaction with light, motions of atoms, making films and patterns, and thermal properties. The computer cluster will be used in a wide variety of educational programs, including computational modeling courses, laboratories and summer research programs.

The International Symposium on the Relations between Homgeneous and Heterogeneous Catalysis is a key forum for scientists throughout the world to explore the fundamental connections between heterogeneous and homogeneous catalytic science and engineering. Northwestern University will host the symposium on July 20-25, 2003, which is the first time for a US location in over a decade. The conference will feature plenary speakers, expert panelists from industry, government, and academia, and paper/poster presentations. New topics for the conference include bio-and supra-molecular catalysis, catalysis as a route to new materials, the intersections between nanoscience and catalysis, green chemistry, and emerging physicochemical or theoretical techniques. Three specific sessions will address new emphases involving international collaboration in "Nanotechnology and Catalysis", "Catalytic Issues in Green Chemistry", and "Graduate Research and Education in Catalysis." Over 200 attendees are expected from academia, industry, and government laboratories. Graduate and postdoctoral students will receive assistance from NSF funding to attend the symposium. This will significantly increase the educational experience of these outstanding young researchers, especially since attendance at the US location is feasible. The strong international aspects of the symposium will advance the student's appreciation of worldwide research in catalysis. Students will have an excellent opportunity to learn about the newest research developments in their areas, dialog with other academic, industrial, governmental researchers, and advance their participation in professional societies.

This project is a joint research and education program between the Materials Research Institute at Northwestern University (NU) and the National Microelectronic Research Center (NMRC) at the University College, Cork, Republic of Ireland. The project addresses design, synthesis, characterization, fundamental understanding, and optimization of molecule-based nanostructured optical materials for the fabrication of photonic devices with a special emphasis on ultra-high speed optical switches. The approach is to study how new ? (2) and ? (3) materials with (or without) plasmon field enhancement can increase the speed and efficiency of photonic switches. Special focus is placed on the synthesis and self-assembly of unusual new ? (3) materials based on fullerenes, metal oxides, novel metallomacrocyles, and nanoparticle resonant field-enhanced p-conjugated polymers having large third- order optical responses. Another focus is on the study of enhanced susceptibilities in excited molecular states for switching. The fundamental scientific aim of this effort involves the preparation, measurement and understanding of nonlinear responses in metastable excited triplet states. The anticipated application is in optical computing and signal processing, based on an enhanced nonlinear response predicted in such metastables. New molecular chromophores, including those with twisted p -systems, will be designed and synthesized. The long-term objectives of the joint program include the development of ultra-compact photonic and plasmonic integrated circuits including ultra-fast (near-sub-picosecond) optical switches using nonlinear effects in nanostructured materials. The project also will advance theoretical understanding of photonic effects in molecular materials. Involvement in the program will enrich the research and education environment of students, teachers, and their colleagues.
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The project addresses fundamental research issues associated with electronic and photonic materials having technological relevance. An important feature of the project is the strong emphasis on education, with emphasis on integration of research and education, and an international collaboration providing both scientific and educational benefits. These include: 1. Interdisciplinary and International research opportunities. 2. The experience of integrating research with education. 3. Science content and curriculum development. 4. Outreach and global dissemination of research and education information. 5. Summer Research Program for science teachers and under-represented students-collaborators will host science teachers and under-represented students in their laboratories to perform summer research. Under the proposed program, these summer participants will also be involved in educational exchange programs between Northwestern University and the NMRC in Ireland. This NSF project is a Cooperative Activity in Materials Research between the NSF and Europe (NSF 02-135). The project is being carried out in collaboration with the University College, Cork, Republic of Ireland.

Funds obtained from this proposal will be used to acquire a 400 MHz NMR spectrometer equipped with the necessary accessories for conducting state-of-the-art solid state NMR materials characterization experiments. The accessories will include a double-resonance, magic angle spinning (MAS) probe, which is essential for many solid state NMR spectroscopic applications, as well as a single-resonance CRAMPS (Combined Rotation and Multiple Pulse Sequence) probe for solid state NMR spectroscopy of the 1H nucleus. This requested instrumentation will provide greatly improved solid state NMR spectroscopic capabilities for studying a wide range samples, hence advancing the interdisciplinary materials research being conducted in a broad range of departments at Northwestern University (NU). Research programs which would immediately benefit from incisive condensed matter NMR characterization capabilities include those studying novel transition metal reagents for organic synthesis, novel opto-electronically active solids for optical communications, data storage, and organic transistors, metal-organic frameworks for efficient energy storage and catalysis, silicon-based cage structures and nanocapsules having unusual architectures, graphene nanoplatelets and carbon nanorods for solid state electronics and high-strength materials, novel structural and barrier polymers, and solid state natural materials such as resins and gums from plant exudates. The more sensitive one- and two-dimensional solid state NMR spectroscopy at ambient and variable temperatures offered by this new instrument will significantly enable far more definitive structural characterization of these materials, leading to a more detailed understanding of their functionality. The ability to conduct these studies in-house with high throughput and rapid feedback will not only allow NU materials research to move forward more expeditiously, but will also provide a more complete educational experience for graduate students who will learn modern solid state NMR spectroscopic techniques in a hands-on manner while applying it to their own research. Additionally, advanced undergraduate courses in the Chemistry, Chemical Engineering, and Materials Science and Engineering programs at NU will introduce experiments with this instrumentation. These educational benefits will spread far beyond NU as graduate and undergraduate students move on to other positions.


Modern Nuclear Magnetic Resonance (NMR) spectroscopy is an extremely powerful technique for understanding the structure and function of solid materials. Funds from this proposal will be used to acquire a state-of-the-art spectrometer for use by a broad community of materials research scientists and their students at Northwestern University. Interdisciplinary research being conducted in many departments will benefit from the structural characterization capabilities offered by the proposed instrument and not currently available to us. The data from this instrument will lead to a better understanding of a wide range of solid state materials currently under study and which are important to the development of more selective, efficient, and environmentally friendly catalytic processes, new materials for energy storage, opto-electronic materials for high-speed communications, data storage, and printed transistors, and stronger, lighter weight structural materials. This requested instrument will also play a major role in educational programs for our graduate and undergraduate students.

Project Summary

Metal-Organic Precursors for High-Temperature Lubrication

Q. J. Wang, T. Marks, and L. M. Keer
Northwestern University

An in-situ novel lubrication approach using a soft metal-organic chemical vapor deposition (MOCVD) process is proposed for accomplishing 1) deposition/replenishment through the in-situ-MOCVD process, 2) solid lubrication at high temperatures for normal operation, 3) liquid metal lubrication at extremely high temperatures for sustained maximum power delivery, and 4) self-healing against thermally induced failures. The proposed research involves synthesizing, characterizing, and evaluating silver-based metal-organic compounds with tailor-made thermal properties and decomposition pathways. It is expected that metal-organic compounds developed with a wide range of decomposition temperatures and different soft metals will be a class of novel high-temperature lubricants. The results of the proposed research will provide a better understanding of the mechanistic nature of silver growth processes on metal surfaces and how such growth depends on precursor ligation, deposition conditions, and deposition technique. A significant advance in high-temperature lubrication would have great economic benefit. Moreover, a highly interactive, interdisciplinary project will provide a challenging environment for student training.

This award by the Inorganic, Bioinorganic, and Organometallic Chemistry Program to Professor Tobin J. Marks of Northwestern University supports studies on both fundamental and technologically-oriented aspects of new catalytic transformations involving lanthanide and related early transition metals. The proposal has been divided into four subtopics: 1) exploratory catalytic metal-heteroelement chemistry, 2) organolanthanide-mediated materials synthesis, 3) multinuclear catalysis and 4) other metals and supporting ligands for f-element catalysis. Titration calorimetry will be used to quantify the strengths of metal-ligand single and multiple bonds and to "anchor" bond enthalpies on an absolute scale. The research includes the study of selective C-N, C-O, C-S, and C-P bond-forming processes, the study of a range of precursor structures, the characterization of reaction rates, selectivities, and substituent effects, as well as the comparison of intramolecular vs. intermolecular processes. These transformations may produce efficient, atom-economical, catalytic processes for the production of fuels, plastics, pharmaceuticals and other commercially-important chemicals. This research also addresses the national need for researchers trained in basic heavy element chemistry for the nuclear industry.

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).

With this award from the Major Research Instrumentation (MRI) program, the Chemistry Department at Northwestern University will acquire a gas chromatograph time-of-flight (GC-TOF) mass spectrometer for use in teaching and research. A variety of research projects will be investigated including: 1) Organo-f-Element Chemistry - Integrated Synthetic, Mechanistic, Catalytic, and Thermochemical Studies; 2) Enzyme Mimics Based on Supramolecular Coordination Assembly; 3) Reticular Networks Forged for Dynamic Processes; 4) Unlocking the Synthetic Potential of N-Allylhydrazones; and, 5) Molecular Spintronics.

Mass spectrometry (MS) is used to identify the chemical composition of a sample and determine its purity by measuring the mass of the molecular constituents in the sample after they are ionized and detected by the mass spectrometer. Chromatography is an isolation technique that precedes the mass spectrometry analysis. It separates a mixture into its constituent chemicals which are then analyzed by the mass spectrometer. These are analytical techniques widely used to characterize the chemical composition of a sample. The mass spectrometer will be used by undergraduate and graduate research students and in undergraduate laboratory classes.

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).

With this award Northwestern University will establish an International Materials Institute (IMI) for Solar Energy Conversion. Although conventional silicon and other semiconductor solar cells have achieved high efficiency for solar energy conversion, their production costs remain high. Organic photovoltaic cells (OPVC) might yield cost-effective green energy for a wide variety of applications. The efforts of this IMI are focused on theory-guided fundamental research on OPVC - new materials design, processing, and device fabrication to understand physical processes and limitations to efficient conversion and storage of solar energy. Northwestern University, Louisiana State University and Argonne National Laboratory along with Tsinghua University in China will form the core partnership to lead the efforts of the IMI. Researchers from 35 more institutions worldwide including USA, China, Australia, Germany, Japan, South Africa, and Taiwan will participate as standing partners. IMI activities include exchange visits of faculty, postdoctoral scholars, and students among core partners, annual symposia and workshops for all partners to exchange research findings and development of a global cyber-based network for year-around communication of solar energy research. The IMI will integrate research and education with a strong focus on global leadership development for graduate students, undergraduate courses on energy conversion topics, teaching modules on solar energy topics for K-12, and inform the public about solar energy conversion and its role in energy conservation via museum and media presentations. A Leadership Council consisting of the lead researchers from core partner institutions will provide oversight and internal assessment of the research and education programs of the IMI. Guidance and external evaluation will be provided by a rotating Technical Advisory Board consisting of representatives from academia, industry and government laboratories.

With this award from the Chemistry Research Instrumentation and Facilities: Multi-user (CRIF:MU) program, Professor Mark Ratner and colleagues Joseph Hupp, Tobin Marks, SonBinh Nguyen and J. Fraser Stoddart from Northwestern University will acquire a 400 MHz spectrometer. The proposal will enhance research training and education at all levels, especially in areas of study such as (a) unlocking the synthetic potential of n-allylhydrazones, (b) bimetallic ethylene polymerization: integrated synthetic, mechanistic, and polymerization studies, and photonics, plasmonics and molecule-based nanomaterials, (c) molecular logic for nanoelectronics, (d) synthesis and characterization of metal-organic frameworks from start to finish, (e) characterization of the surface of colloidal quantum dot (QDs) and its correspondence to their electronic and optical properties, and (f) design and synthesis of novel catalysts for green chemistry and environmental remediation.

Nuclear Magnetic Resonance (NMR) spectroscopy is one of the most powerful tools available to chemists for the elucidation of the structure of molecules. It is used to identify unknown substances, to follow the progress of chemical reactions, to characterize specific arrangements of atoms within molecules, and to study the dynamics of interactions between molecules in solids and in solution. Access to state-of-the-art NMR spectrometers is essential to carry out frontier chemistry related research and to train students in modern research techniques. The results from these NMR studies will have an impact on organic, materials, electronics, environmental and bioorganic chemistry research at Northwestern University. The instrument will be available to users at other institutions including Harold Washington College and Roosevelt University. The resources will be used not only for research activities but also for research training of undergraduate and graduate students including those from underrepresented groups.

With this award, the Chemical Catalysis Program in the Chemistry Division is funding Dr. Tobin Marks of Northwestern University to discover, understand, and optimize chemical transformations involving metal catalysts. Such processes are of central importance to the chemical enterprise and include efficient, atom-economical, and sustainable catalytic processes for producing fuels, plastics, pharmaceuticals, and other economically important chemicals. This project involves four interlinked focus areas that integrate research and education, and deal with fundamental and technologically-oriented aspects of new catalytic reactions utilizing earth-abundant metal catalysts. Computational analysis is being used to understand the catalytic transformations, and most importantly, to discover new ones. A parallel goal being accomplished is the elucidation of principals for new, efficient, useful, atom-efficient, and environmentally "green" catalytic processes. Participation in this multifaceted/multidisciplinary project, including interactions with industrial scientists, is preparing students with diverse backgrounds for careers in industry, government laboratories, and academia.

Professor Marks is studying four research areas: 1) Catalytic hydroelementation to discover, characterize, and understand atom-efficient processes that mediate heteroelement-hydrogen additions to carbon-carbon saturation. This project is focusing on unexplored, lanthanide-catalyzed processes that couple multiple catalytic bond-forming events (cascades), that utilize unsaturated heterocycles (dearomatization), that invent new ways to form oxygen-carbon and sulfur-carbon bonds, and provide actinide catalysts which mediate new bond-forming sequences. 2) Electrophilic catalysis in polar media to study hydroelementation and its reverse using recyclable, highly electrophilic lanthanide catalysts in non-volatile, recyclable ionic liquids or other polar solvents to effect new hydroelementation processes and to develop catalytic reactions that, when coupled to hydrogenation, achieve the microscopic reverse: cleaving carbon-oxygen, carbon-nitrogen, and carbon-sulfur bonds with hydrogen. This research has implications for more efficient processing of sustainable biofuels and other natural resources. 3) Catalytic materials synthesis to use lanthanide, actinide, and related transition metal catalysts in investigating the coupling of olefin polymerization processes with hydroelementation, to produce heteroatom-functionalized polymers, thereby introducing polar functionality at polymer chain ends. 4) Multinuclear catalysis to alter the course of catalytic polymerization and copolymerization reactions by poising two catalytic centers in close proximity. Ideally, such cooperativity effects are likely to alter both the rates and selectivities of kinetic events that control polymer architecture, mechanical properties, and processing characteristics.

Communications systems such as WiFi, GPS, wireless sensor networks, and radio frequency electronics are critical to the nation?s infrastructure and have had a transformative impact on daily life. However, existing applications of wireless technologies are often limited by the power consumption and speed of the underlying electronic switches, or transistors, that send and receive signals. Furthermore, current classes of transistors must be integrated into complex circuits to perform simple functions. This award supports the fundamental research necessary to make new classes of transistors that can improve the performance of existing communications technologies and open up new applications by enabling simplified circuit designs on flexible substrates. The development of inexpensive and scalable approaches to new transistor materials will facilitate the incorporation of these devices into new technologies. Computer models of novel transistors and communications circuits will be shared with industry partners to facilitate the transfer of knowledge and capabilities to industry, growing the high-tech economy. Outreach programs including cooperation with the Chicago Museum of Science and Industry will recruit a broad group of young people to careers in science and technology crucial to the nation?s economy and defense.

The objective of the proposed work is to create, characterize, understand, and exploit new classes of electronic and optoelectronic devices by integrating promising two-dimensional monolayer transition metal dichalcogenides with other low dimensional semiconductors including p-type organic semiconductors, sorted semiconducting single walled carbon nanotubes, and other two-dimensional materials. The project will fabricate novel ultrathin p-n heterojunctions of mixed dimensionality that exhibit unique and quantitatively advantageous properties arising from gate transparency and flexibility, and characterize the devices with advanced scanned probe techniques in addition to conventional current and capacitance versus voltage measurements. Custom chemical precursors will be designed and synthesized with the goal of achieving scalable growth and fabrication of ultrathin dichalcogenides by atomic layer deposition over large areas at reduced temperatures. To understand how the device physics leads to new properties and circuit performance, phenomenological models will be integrated into industry accepted nanodevice simulators, and a compact model will be developed. The fundamental knowledge and predictive models of ultrathin heterojunctions will expand engineering frontiers through quantitative understanding of charge transport, the demonstration of novel device characteristics, such as the recently discovered anti-ambipolar behavior, and the exploitation of these behaviors to create novel electronic circuits on flexible substrates with simpler designs and fewer elements than conventional unipolar field effect transistor-based circuits.