The research in the Rubinstein Group is in the field of polymer theory and computer simulations. The unique properties of polymeric systems are due to the size, topology and interactions of the molecules they are made of. Our goal is to understand the properties of various polymeric systems and to design new systems with even more interesting and useful properties. Our approach is based upon building and solving simple molecular models of different polymeric systems. The models we develop are simple enough to be solved either analytically or numerically, but contain the main features leading to unique properties of real polymers. Computer simulations of our models serve as an important bridge between analytical calculations and experiments.
Research in the Nicewicz Group focuses on developing new catalysts and methods for organic synthesis. In particular, our group seeks to harness the power of photoinduced electron transfer processes to drive the development of new asymmetric bond forming reactions. Additionally, we seek to apply these new reactions to the synthesis of biologically-active, complex natural products.
Nancy Allbritton, the Paul Debreczeny Distinguished Professor of Chemistry and Chair of the UNC/NC State joint Department of Biomedical Engineering, has been named a fellow of the National Academy of Inventors. The honor is awarded to academic inventors who have a prolific spirit of innovation in creating outstanding inventions that have made a tangible impact on quality of life, economic development and the welfare of society. Allbritton was also recently elected a fellow of the American Association for the Advancement of Science, AAAS.
The innovators elected as NAI fellows are named inventors on U.S. patents and were nominated by their peers for outstanding contributions to innovation in areas such as patents and licensing, innovative discovery and technology, significant impact on society, and support and enhancement of innovation.
Francis Preston Venable Professor of Chemistry, Joseph Templeton, is the recipient of this year's Thomas Jefferson award, which was presented to him by Chancellor Folt at a recent Faculty Council meeting. "I would just like to add from my own chance to work so closely with Professor Templeton the last year how deserving and wonderful this award is," said Chancellor Folt.
The Thomas Jefferson Award was established in 1961 by the Robert Earll McConnell Foundation. It is presented annually to "that member of the academic community who through personal influence and performance of duty in teaching, writing, and scholarship has best exemplified the ideals and objectives of Thomas Jefferson." This award is, according to Department Chair, Professor Valerie Ashby, "a well-deserved honor for Professor Templeton that recognizes the many forms of his contributions to the university throughout his career."
To further improve the physical strength and biomedical applicability of bioceramics built on hydroxyapatite-gelatin, HAp-Gel, and siloxane sol-gel reactions, the You group incorporated mussel adhesive inspired polydopamine, PD, into the original composite based on HAp-Gel cross-linked with siloxane, discovered by Dr. Ching-Chang Ko at the UNC Dental School.
Surprisingly, with the addition of PD, the team of You/Ko observed that the processing conditions and temperatures play important roles in the structure and performance of these materials. A systematic study to investigate this temperature dependence behavior discloses that the rate of crosslinking of silane during the sol–gel process is significantly influenced by the temperature, whereas the polymerization of the dopamine only shows minor temperature dependence. With this discovery, reported in the Journal of Materials Chemistry B, the team report an innovative thermal process for the design and application of these biocomposites..
As announced by Israeli Prime Minister Benjamin Netanyahu on October 6th, Arey Distinguished Professor of Chemistry, Thomas Meyer, is one of two winners of the 2014 Eric and Sheila Samson Prime Minister's Prize for Innovation in Alternative Fuels for Transportation. Professor Meyer is recognized as a world leader in solar fuel research.
The $1 million prize is awarded for breakthrough work into converting solar energy into electricity capable of powering transportation. "We are making a major multi-year effort so that we will not be dependent on fluctuations in the price of oil," Netanyahu said. "This prize gives the researchers true appreciation for their efforts." The Eric and Sheila Samson Prize, totaling $1 million, is the world’s largest monetary prize awarded in the field of alternative fuels, and is granted to scientists who have made critical advancements."
Congratulations to Dr. Meyer on receiving such a prestigious international honor," said UNC Chancellor Carol L. Folt. "Dr. Meyer is a superb example of the kind of innovation we champion here at UNC, using research to solve the world's most pressing problems. By pairing a basic scientific knowledge of photosynthesis with the latest advances in nanotechnology, Dr. Meyer and his team are bringing the world closer than ever to making solar energy a practical, reliable power source."
A new small molecule receptor, A2N, has been identified that binds specifically to trimethyllysine, Kme3, with sub-micromolar affinity. This receptor, as published in Organic & Biomolecular Chemistry was discovered by Nicholas Pinkin and Marcey Waters in the Waters Group, through the iterative redesign of a monomer known to incorporate through dynamic combinatorial chemistry, DCC, into a previously reported receptor for Kme3, A2B. In place of monomer B, the newly designed monomer N introduces an additional cation–Π interaction into the binding pocket, resulting in more favorable binding to Kme3 amounting to a ten-fold improvement in affinity and a five-fold improvement in selectivity over Kme2.
This receptor exhibits the tightest affinity and greatest selectivity for Kme3-containing peptides reported to date. Comparative studies of A2B and A2N provide mechanistic insight into the driving force for both the higher affinity and higher selectivity of A2N, indicating that the binding of Kme3 to A2N is both enthalpically and entropically more favorable. This work demonstrates the ability of iterative redesign coupled with DCC to develop novel selective receptors with the necessary affinity and selectivity required for biological applications.
Developing novel materials and device architectures to further enhance the efficiency of polymer solar cells requires a fundamental understanding of the impact of chemical structures on photovoltaic properties. Given that device characteristics depend on many parameters, deriving structure/property relationships has been very challenging.
Through an international collaboration, members of the You Group discovered that a single parameter, hole mobility, determines the fill factor of bulk heterojunction photovoltaic devices in a series of copolymers with varying amount of fluorine substitution. The continuous increase of hole mobility upon further fluorination is related to a preferential face-on orientation and improved pi-pi stacking of the polymer backbones. The results shows the potential of properly-designed polymers to enable high fill factors in thick devices, as required by mass production technologies. These significant results appeared in JACS, and were also featured in JACS Spotlights.
At the Department of Chemistry, we feel strongly that diversity is crucial to our pursuit of academic excellence, and we are deeply committed to creating a diverse and inclusive community. We support UNC's policy, which states that "the University of North Carolina at Chapel Hill is committed to equality of opportunity and pledges that it will not practice or permit discrimination in employment on the basis of race, color, gender, national origin, age, religion, creed, disability, veteran's status, sexual orientation, gender identity or gender expression."