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Professor Francesco Evangelista

Professor Francesco Evangelista
Department of Chemistry
Emory University

Abstract

Accelerating Quantum Chemistry with Quantum Computers

An outstanding challenge in modern electronic structure theory is simulating chemistry problems that involve open-shell species, such as bond-breaking reactions, photochemical processes, transition metal catalysis, and molecular magnetism. A common feature of all of these problems is the emergence of strong electron correlation effects or quantum mechanical entanglement. Modeling strong correlation is considered a hard problem since, in the most general case, it has a computational cost that scales exponentially with the number of electrons. Quantum computation offers an intriguing approach to accelerate the simulation of strongly correlated electrons. With sustained progress in quantum device engineering, there is a realistic expectation that medium-sized quantum computers (100-200 qubits) will be available in the near future. These devices could enable computations on systems that are classically intractable and open up new applications of computational chemistry. This talk will give an overview of quantum computing approaches for quantum chemistry and describe my group's efforts to develop hybrid quantum-classical methods that combine renormalization group theory and quantum computing.

Professor Evangelista

Professor Evangelista's theoretical chemistry research focus is the development of new electronic structure methods to address chemical phenomena that are not well understood. Having a predilection for rigorous theoretical approaches that follow from first principles, his research group is particularly fond of many-body methods (e.g. coupled cluster theory), but doesn't shy away from density functional theory.

Evangelista earned his doctorate in chemistry from the University of Georgia, his master's in physical chemistry from the University of Pisa, and his undergraduate degree from the Scuola Normale Superiore di Pisa. He also was an Alexander von Humboldt Junior Fellow in Mainz, Germany, and a post-doctoral associate at Yale University. He has been a professor at Emory University since 2013.

Professor Nandini Ananth

Professor Nandini Ananth
Department of Chemistry & Chemical Biology
Cornell University
Host: Professor Aaron Massari

Abstract

 A Study of Singlet Fission in Bipentacenes

We investigate the mechanisms of Singlet Fission (SF), a phenomenon where an initial photo-excited singlet state spontaneously evolves into a correlated triplet state that can subsequently decorrelate into two triplets. We probe different aspects SF in bipentacenes through both high-level electronic structure studies and simple semi-empirical theories to arrive at rules for identifying SF-active chromophores that absorb intensely in the visible region. Further, we study the recombination rates of the correlated triplet state produced by SF using a new, singularity-free formulation for nonradiative rates. We also show that it is possible to identify key vibronic modes in the recombination process. Finally, we discuss the real-time dynamic methods we have developed to enable atomistic simulations of SF.

Professor Ananth

Professor Ananth's group seeks to understand the molecular origin of chemical selectivity in natural and synthetic systems using theoretical simulation techniques derived from the principles of quantum and classical mechanics. Research interests include:

  • Developing semiclassical and path-integral based model dynamics to simulate interesting chemistry in the condensed-phase.
  • Developing approximate methods for quantum dynamics that are able to incorporate quantum effects like zero-point energy, tunneling, and coherence and to describe electronically nonadiabatic processes, while retaining the favorable scaling in computational cost with system size exhibited by classical molecular dynamics simulations.
  • Understanding the molecular origin of chemical selectivity in natural and synthetic systems.
  • Investigating exciton chemistry in organic photovoltaics, multi-electron chemistry in tri-metal-center transition metal complexes, and vibrationally promoted hot-electron chemistry in reactions at metal surfaces.

Goals are to use a combination of theory, electronic structure, and quantum dynamics to 1) uncover the detailed mechanisms of novel charge and energy transfer phenomena, 2) identify productive reaction pathways/intermediates as well as competing loss mechanisms, 3) isolate significant factors, such as chemical environment, relative geometries, and temperature that determine dominant pathways, 4) construct experimentally verifiable hypotheses to enhance charge/energy transport properties of specific materials, and 5) build a database of transferable design principles that can be used predictively in the development of novel materials.

Professor Ananth

Nandini Ananth was born in Chennai, India. She attended Stella Maris College in Chennai, and graduated with a bachelor's degree in chemistry. She then joined the master's program in chemistry at the Indian Institute of Technology Madras. Here she developed a strong interest in quantum mechanics and carried out research on implementing logic gates for quantum computing using Nuclear Magnetic Resonance. During this time, she also received a Summer Research Fellowship from the Jawaharlal Nehru Center for Advanced Scientific Research and was introduced to semiclassical dynamics at the Indian Institute of Science, Bangalore. This further solidified her interest in theoretical chemistry and chemical dynamics. Ananth moved to the United States to pursue doctoral research at the University of California, Berkeley, working on developing semiclassical methods to model quantum dynamical behavior in complex chemical reactions. Upon graduation, she accepted a position as post-doctoral scholar at the California Institute of Technology, Pasadena, where her research focused on developing path-integral methods for the simulation of electronically nonadiabatic processes in the condensed phase. She joined the faculty of the Department of Chemistry and Chemical Biology at Cornell University in 2012.

Professor Omar Yaghi

Kolthoff Lecture #1
Professor Omar Yaghi
Department of Chemistry
University of California, Berkeley
Host: Professor Theresa Reineke

Research

Professor Omar Yaghi's work encompasses the synthesis, structure and properties of inorganic and organic compounds and the design and construction of new crystalline materials. He is widely known for pioneering several extensive classes of new materials termed metal-organic frameworks, covalent organic frameworks, and zeolitic imidazolate frameworks. These materials have the highest surface areas known to date, making them useful in clean energy storage and generation. Specifically, applications of his materials are found in the storage and separation of hydrogen, methane, and carbon dioxide, and in clean water production and delivery, supercapacitor devices, proton and electron conductive systems. The building block approach he developed has led to an exponential growth in the creation of new materials having a diversity and multiplicity previously unknown in chemistry. He termed this field 'Reticular Chemistry' and defines it as stitching molecular building blocks into extended structures by strong bonds.

Professor Yaghi

Professor Yaghi received his Bachelor of Science degree from State University of New York-Albany, and doctorate from the University of Illinois-Urbana. He was a National Science Foundation Post-doctoral fellow at Harvard University. He has been on the faculties of Arizona State University, University of Michigan, and UCLA. He is currently the James and Neeltje Tretter Chair Professor of Chemistry at the University of California, Berkeley, and a senior faculty scientist at Lawrence Berkeley National Laboratory. He is the founding director of the Berkeley Global Science Institute. He is also co-director of the Kavli Energy NanoScience Institute, and the California Research Alliance by BASF.

Kolthoff Lectureship in Chemistry

Izaak Maurits Kolthoff was born on February 11, 1894, in Almelo, Holland. He died on March 4, 1993, in St. Paul, Minnesota. In 1911, he entered the University of Utrecht, Holland. He published his first paper on acid titrations in 1915. On the basis of his world-renowned reputation, he was invited to join the faculty of the University of Minnesota’s Department of Chemistry in 1927. By the time of his retirement from the University in 1962, he had published approximately 800 papers. He continued to publish approximately 150 more papers until his health failed. His research, covering approximately a dozen areas of chemistry, was recognized by many medals and memberships in learned societies throughout the world, including the National Academy of Sciences and the Nichols Medal of the American Chemical Society. Best known to the general public is his work on synthetic rubber. During World War II, the government established a comprehensive research program at major industrial companies and several universities, including Minnesota. Kolthoff quickly assembled a large research group and made major contributions to the program. Many of Kolthoff’s graduate students went on to successful careers in industry and academic life and, in turn, trained many more. In 1982, it was estimated that approximately 1,100 Ph.D. holders could trace their scientific roots to Kolthoff. When the American Chemical Society inaugurated an award for excellence in 1983, he was the first recipient.

Professor Omar Yaghi

Kolthoff Lecture #2
Professor Omar Yaghi
Department of Chemistry
University of California, Berkeley
Host: Professor Theresa Reineke

Research

Professor Omar Yaghi's work encompasses the synthesis, structure and properties of inorganic and organic compounds and the design and construction of new crystalline materials. He is widely known for pioneering several extensive classes of new materials termed metal-organic frameworks, covalent organic frameworks, and zeolitic imidazolate frameworks. These materials have the highest surface areas known to date, making them useful in clean energy storage and generation. Specifically, applications of his materials are found in the storage and separation of hydrogen, methane, and carbon dioxide, and in clean water production and delivery, supercapacitor devices, proton and electron conductive systems. The building block approach he developed has led to an exponential growth in the creation of new materials having a diversity and multiplicity previously unknown in chemistry. He termed this field 'Reticular Chemistry' and defines it as stitching molecular building blocks into extended structures by strong bonds.

Professor Yaghi

Professor Yaghi received his Bachelor of Science degree from State University of New York-Albany, and doctorate from the University of Illinois-Urbana. He was a National Science Foundation Post-doctoral fellow at Harvard University. He has been on the faculties of Arizona State University, University of Michigan, and UCLA. He is currently the James and Neeltje Tretter Chair Professor of Chemistry at the University of California, Berkeley, and a senior faculty scientist at Lawrence Berkeley National Laboratory. He is the founding director of the Berkeley Global Science Institute. He is also co-director of the Kavli Energy NanoScience Institute, and the California Research Alliance by BASF.

Kolthoff Lectureship in Chemistry

Izaak Maurits Kolthoff was born on February 11, 1894, in Almelo, Holland. He died on March 4, 1993, in St. Paul, Minnesota. In 1911, he entered the University of Utrecht, Holland. He published his first paper on acid titrations in 1915. On the basis of his world-renowned reputation, he was invited to join the faculty of the University of Minnesota’s Department of Chemistry in 1927. By the time of his retirement from the University in 1962, he had published approximately 800 papers. He continued to publish approximately 150 more papers until his health failed. His research, covering approximately a dozen areas of chemistry, was recognized by many medals and memberships in learned societies throughout the world, including the National Academy of Sciences and the Nichols Medal of the American Chemical Society. Best known to the general public is his work on synthetic rubber. During World War II, the government established a comprehensive research program at major industrial companies and several universities, including Minnesota. Kolthoff quickly assembled a large research group and made major contributions to the program. Many of Kolthoff’s graduate students went on to successful careers in industry and academic life and, in turn, trained many more. In 1982, it was estimated that approximately 1,100 Ph.D. holders could trace their scientific roots to Kolthoff. When the American Chemical Society inaugurated an award for excellence in 1983, he was the first recipient.

Professor Omar Yaghi

Kolthoff Lecture #3
Professor Omar Yaghi
Department of Chemistry
University of California, Berkeley
Host: Professor Theresa Reineke

Research

Professor Omar Yaghi's work encompasses the synthesis, structure and properties of inorganic and organic compounds and the design and construction of new crystalline materials. He is widely known for pioneering several extensive classes of new materials termed metal-organic frameworks, covalent organic frameworks, and zeolitic imidazolate frameworks. These materials have the highest surface areas known to date, making them useful in clean energy storage and generation. Specifically, applications of his materials are found in the storage and separation of hydrogen, methane, and carbon dioxide, and in clean water production and delivery, supercapacitor devices, proton and electron conductive systems. The building block approach he developed has led to an exponential growth in the creation of new materials having a diversity and multiplicity previously unknown in chemistry. He termed this field 'Reticular Chemistry' and defines it as stitching molecular building blocks into extended structures by strong bonds.

Professor Yaghi

Professor Yaghi received his Bachelor of Science degree from State University of New York-Albany, and doctorate from the University of Illinois-Urbana. He was a National Science Foundation Post-doctoral fellow at Harvard University. He has been on the faculties of Arizona State University, University of Michigan, and UCLA. He is currently the James and Neeltje Tretter Chair Professor of Chemistry at the University of California, Berkeley, and a senior faculty scientist at Lawrence Berkeley National Laboratory. He is the founding director of the Berkeley Global Science Institute. He is also co-director of the Kavli Energy NanoScience Institute, and the California Research Alliance by BASF.

Kolthoff Lectureship in Chemistry

Izaak Maurits Kolthoff was born on February 11, 1894, in Almelo, Holland. He died on March 4, 1993, in St. Paul, Minnesota. In 1911, he entered the University of Utrecht, Holland. He published his first paper on acid titrations in 1915. On the basis of his world-renowned reputation, he was invited to join the faculty of the University of Minnesota’s Department of Chemistry in 1927. By the time of his retirement from the University in 1962, he had published approximately 800 papers. He continued to publish approximately 150 more papers until his health failed. His research, covering approximately a dozen areas of chemistry, was recognized by many medals and memberships in learned societies throughout the world, including the National Academy of Sciences and the Nichols Medal of the American Chemical Society. Best known to the general public is his work on synthetic rubber. During World War II, the government established a comprehensive research program at major industrial companies and several universities, including Minnesota. Kolthoff quickly assembled a large research group and made major contributions to the program. Many of Kolthoff’s graduate students went on to successful careers in industry and academic life and, in turn, trained many more. In 1982, it was estimated that approximately 1,100 Ph.D. holders could trace their scientific roots to Kolthoff. When the American Chemical Society inaugurated an award for excellence in 1983, he was the first recipient.

Professor Michael Fayer

Professor Michael Fayer
Department of Chemistry 
Stanford University
Host: Professor Aaron Massari

Abstract

Dynamics in concentrated LiCl and HCl solutions

Aqueous salt solutions occur widely in systems ranging from industrial processes to biological materials. Prominent examples include batteries and desalinization. The properties of aqueous electrolyte solutions involve the dynamics of water and the dynamics of ions.  A closely relate problem is proton transfer in acid solutions. Proton transfer in water is ubiquitous and a critical elementary event which, via proton hopping between water molecules, enables protons to diffuse much faster than other ions. While there have been a vast number of experiments and molecular dynamics simulations investigating proton hopping in water, a direct experimental observation of proton hopping has remained elusive due to its ultrafast nature and the lack of direct experimental observables. The dynamics of the formation and dissociation of complexes of Li+ and water with methylthiocyanate (MeSCN) in very concentration LiCl solutions are explicated using two dimensional infrared (2D IR) Chemical Exchange Spectroscopy.  The CN stretch is used as the vibrational probe.  2D IR spectral diffusion measurement show that MeSCN accurately reports on the hydrogen bond dynamics in pure water, making it an excellent probe of dynamics in aqueous systems. Water forms a hydrogen bond and Li+ associates with the nitrogen lone pair of the CN moiety of MeSCN.  These two complexes display distinct CN peaks in the FT-IR spectrum.  2D IR is used to directly measure the chemical exchange of water and Li+ with the nitrogen lone pair of the CN moiety.  2D IR is also used to measure the spectral diffusion, which provides information on the dynamic of the concentrated salt solutions.  In pure water, the spectral diffusion gives rise to a biexponential decay of the 2D IR data.  In the salt solutions, triexponentials are observe.  The slowest component is assigned to the time for ion clusters to randomize. 2D IR Chemical Exchange Spectroscopy was also used to extract the chemical exchange rates between hydronium and water in HCl solutions using MeSCN.  Ab initio molecular dynamics simulations demonstrate that the chemical exchange is dominated by proton hopping. The observed experimental and simulated acid concentration dependences as well as a number of factors obtained from the simulations and spectral diffusion measurements make it possible to extrapolate the measured single step proton hopping time in concentrated HCl to the dilute limit. Within error the 2D IR measure hopping time yields the same value as inferred from measurements of the proton diffusion constant.  It is found that the dilute limit, the proton hopping time is the same as the time for concerted H-bond rearrangement of the extended H-bond network in pure water.  The results indicate that the H-bond rearrangement of the water network in which hydronium ions are embedded triggers proton hopping.

Professor Fayer

Professor Fayer earned his bachelor and master's degrees from the University of California, Berkeley. He was a professor of physics at the University of Grenoble, before joining the faculty at Stanford University. He is the David Mulvane Ehrsam and Edward Curtis Franklin professor of chemistry at Stanford University.

Researchers in Professor Fayer's lab are using ultrafast 2D IR vibrational echo spectroscopy and other multi-dimensional IR methods, which they have pioneered, to study dynamics of molecular complexes, water confined on nm lengths scales with a variety of topographies, molecules bound to surfaces, ionic liquids, and materials such as metal organic frameworks and porous silica. They are also studying dynamics in complex liquids, in particular room temperature ionic liquids, liquid crystals, supercooled liquids as well as in influence of small quantities of water on liquid dynamics. In addition, Professor Fayer is studying photo-induced proton transfer in nanoscopic water environments such as polyelectrolyte fuel cell membranes, using ultrafast UV/Vis fluorescence and multidimensional IR measurements to understand the proton transfer and other processes and how they are influenced by nanoscopic confinement. 

Bryce L. Crawford Jr.

Bryce L. Crawford Jr. was a renowned Department of Chemistry professor and scientist. He died in September 2011, at the age of 96. He joined the department in 1940, and became a full professor of physical chemistry in 1946. He was chair of the department from 1955 to 1960, and was dean of the graduate school from 1960 to 1972. He retired in 1985. He loved studying molecular vibrations and force constants, and the experimental side of molecular spectroscopy and molecular structure. During World War II, Crawford worked in research on rocket propellants, making significant contributions to rocketry, and the development of solid propellants for the much larger rockets that evolved after the war. Crawford received many honors during his career, including the prestigious American Chemical Society Priestley Medal; and being named a Fellow of the Society for Applied Spectroscopy, a Guggenheim Fellow at the California Institute of Technology, and a Fulbright Fellow at Oxford University. He held the distinction of membership in three honorary science academies, and was actively involved in many professional associations. 
 

Professor Ekaterina Pletneva

Professor Ekaterina Pletneva
Department of Chemistry
Dartmouth College
Host: Professor Ambika Bhagi-Damodoran

Abstract

Ligands, Protons, Neighboring Redox Centers, and Protein Fold in Redox Reactions of Heme Proteins

Electron-transfer reactions are essential to function of heme proteins as enzymes and electron carriers. In many of these systems the movement of electrons is coupled to other processes such as changes in protonation and protein conformation. Further, hemes are often incorporated into strings of multiple redox centers and their redox properties are strongly affected by their redox neighbors. Our understanding of these important redox-linked processes is incomplete, in part because they cannot be always readily observed. We employ a number of approaches to probe these elusive phenomena in c-type cytochromes and their relevance to biological redox mechanisms.

A small protein cytochrome c (cyt c) with its flexible coordination loop offers opportunities for engineering differently-ligated heme proteins within the cyt c scaffold. We have engineered a variety of switchable proteins in which the interchanging heme iron ligands are Met, Lys, Cys, and His. Analysis of protein stability demonstrates that the protein scaffold and the polypeptide interactions with the solvent play an important role in stabilizing particular heme coordination. Ligand exchange and accompanying protein rearrangements control the rates of redox reactions in these systems. Variations in the identity and location of the dissociating or incoming ligand alter reaction rates by orders of magnitude. Protonation of the heme iron ligands and neighboring groups modify redox reactivity of our model proteins. We show that enthalpies of protonation from isothermal titration calorimetry can be used to identify the number of involved protons and sites of protonation (deprotonation) in protein redox reactions. Finally, our in vitro and in vivo studies of bacterial electron carriers cyt c4, proteins with two heme groups, illustrate the role of the diheme architecture in tuning the electron injection efficiency of these proteins in their ET reaction with cbb3 oxidases.

Professor Pletneva

Heme proteins are the main subjects of Professor Pletneva's research. In particular, researchers in her group have been focusing on ligand substitution reactions at the heme as a common platform for switching the protein structure and redox reactivity in signaling processes. They are investigating conformational properties of cytochrome c in apoptosis and correlate them to the protein peroxidase activity, which is critical for execution of this cellular pathway. We are also studying redox reactivity and folding of native sensors and engineered "switchable" proteins, in which changes in the oxidation state of the heme are linked to heme ligand substitution resulting in protein conformational rearrangements.

Professor Teri Odom

Professor Teri Odom
Department of Chemistry
Northwestern University
Host: Professor Christy Haynes

Professor Teri Odom's group focuses on “making precious metals more precious” by controlling the size and shape of noble metals at the nanoscale. Her group's strategies include the development of new nanofabrication tools to create three-dimensional architectures with structural function that can span three-orders of magnitude simultaneously. We are also pursuing simple and scalable approaches to synthesize anisotropic particles. To understand the details of how light interacts with these structures, they use modeling to calculate the optical properties of single particles as well as the collective effects of assemblies of nanoparticles. Applications of these unique materials include nanomedicine, photovoltaics, sensing, and imaging.

Professor Odom

Professor Odom is the Charles E. and Emma H. Morrison Professor of Chemistry, chair of the Department of Chemistry, and professor of Materials Science and Engineering at Northwestern University. She is editor-in-chief or Nano Letters. She earned her bachelor's degree in chemistry from Stanford University, her doctorate in chemical physics from Harvard University, and was a post-doctoral researcher at Harvard.

Albert J. Moscowitz Memorial Lectureship

The Albert J. Moscowitz Memorial Lectureship in Chemistry was established by friends and colleagues of Professor Albert J. Moscowitz (1929-1996) to honor his many contributions to molecular spectroscopy. He was known for his research on the interpretation of optical rotation and circular dichroism spectra in terms of the structures of chiral molecules. In collaboration with colleagues in the medical sciences, he developed important applications of his methods to biomedical systems. Throughout his career, Moscowitz held numerous visiting professorships at other universities, and served on the editorial boards of the leading journals in chemical physics. His work was honored by election as Foreign Member of the Danish Royal Academy of Sciences and Letters, and as a Fellow of the American Physical Society.

Past Albert J. Moscowitz lecturers include Bruce Berne, Columbia University (2000), R. Stephen Berry, University of Chicago (1998), Jean-Luc Bredas, University of Arizona (2002), Mike Duncan, University of Georgia (2010), Crim F. Fleming, University of Wisconsin (2006), C. Daniel Frisbie, University of Minnesota (1999), Mike Frisch, Gaussian (2008), Anthony Legon, University of Bristol (2013), Marsha Lester, University of Pennsylvania (2011), Frank Neese, Max-Planck Institute for Chemical Energy Conversion (2014), Stuart Rice, University of Chicago (2000), Peter Rossky, University of Chicago (2006), Giacinto Scoles, University of Princeton (2004), Benjamin Schwartz, University of California, Los Angeles (2007), Hirata So, University of Illinois, Urbana-Champaign (2011), Walter Thiel, Max Plank Institute, Muelhiem (2002), Zhen-Gang Wang, CalTech (2014), Georg Kresse, University of Vienna (2016), Emily A. Carter, Princeton University (2017), Martin Moskovits, University of California, Santa Barbara (2018), and Veronique Van Speybroeck, Ghent University (2019).

Professor Paul Anastas

Professor Paul Anastas
School of Forestry & Environmental Studies
Yale University

Paul T. Anastas is the Teresa and H. John Heinz III Professor in the Practice of Chemistry for the Environment and the director of the Center for Green Chemistry & Green Engineering at Yale University. He has appointments in the School of Forestry and Environmental Studies, Department of Chemistry, and Department of Chemical Engineering. 

Anastas took public service leave from Yale to serve as the assistant administrator for the US Environmental Protection Agency and the Agency Science Advisor from 2009-2012. From 2004 -2006, he served as director of the ACS Green Chemistry Institute in Washington, D.C. He was previously the assistant director for the Environment in the White House Office of Science and Technology Policy where he worked from 1999-2004. Trained as a synthetic organic chemist, Anastas received his doctorate from Brandeis University and worked as an industrial consultant.

He is credited with establishing the field of green chemistry during his time working for the U.S. Environmental Protection Agency as the chief of the Industrial Chemistry Branch and as the director of the U.S. Green Chemistry Program. Anastas has published widely on topics of science through sustainability including eleven books, such as Benign by Design, Designing Safer Polymers, Green Engineering, and his seminal work with co-author John Warner, Green Chemistry: Theory and Practice.