This program is supported by the DMR Solid State and Materials Chemistry Program and the CHE Macromolecular, Supramolecular, and Nanochemistry Program.
This effort is directed at the synthesis of functional organic materials and methods for their assembly. Specific themes include the organization of liquid crystalline materials using novel molecular shapes such as rigid triptycene units to enhance liquid crystal alignment. Similar organizational forces can be applied at surfaces and investigations focusing on large skeletal rearrangements caused by specific photochemical reactions will be used to create specific surface alignments. In the area of molecular semiconductors, investigations of the role of long-range and short-range order on the electronic transport properties will be performed. Different global alignments in devices seek to determine if combined Pt dz2 and p-orbital interactions can lead to high mobility in oriented soft crystal phases. Other investigations will focus on open-shell organic materials in liquid crystals. Polyradicals that are strongly electronically coupled intramolecularly will be interrogated to examine if magnetic ordering can play a role in electron transport (i.e. magnetoresistance). Complex polycyclic carbon network materials will be synthesized using Diels Alder reactions in an effort to create higher acene structures containing phenylene units and the synthesis of carbon nanotubes.
NON-TECHNICAL SUMMARY:
Molecular based electronic materials and associated technology is rapidly becoming part of everyday life. Presently, the impact of these technologies is limited by the intrinsic performance of the materials. This research will push forward new design paradigms that seek to produce materials with enhanced electronic transport. It will further develop materials having new types of electronic interactions that can lead to new physical phenomena that can be the basis of future technologies. The students trained in this effort will be prepared to contribute to this emerging industry. In addition, the PI will continue his efforts to create higher diversity in the workforce by continuing to promote and organize workshops that seek to empower the scientific careers of disadvantaged Americans.
Organic electronic materials have many applications and will be an increasing component of the innovation economy of the United States. Realizing the full potential of these emerging materials requires new science and technology, such as was undertaken in this NSF funded program focused on novel functional materials and organizational principles. Specifically, this research created new approaches by which ordered fluids (liquid crystals) and functional nanostrutures can be used in the creation of sensory and electronic materials. Both "bottom-up" as well as "top-down" approaches were developed for the creation of these materials. Bottom-up approaches refer to extending molecular synthesis to generate/assemble larger structures. Top-down approaches represent situations wherein new synthetic methods are applied to pre-formed nanomaterials. Technologies to come from this work have the potential to find commercial applications in the formation of chemical sensors and high performance organic electronics. This proposal also supported the education of broad-minded graduate students and undergraduates and the PI supports an educational model that provides students with a broad, self-reliant technical background as well as education in leadership, management, and entrepreneurship. The PI has a deep commitment to increasing diversity in science and engineering and continues to organize the Future Faculty Workshop, which prepares underrepresented groups to compete for academic careers.
