Large Hyperpolarizabilities at Telecommunication-Relevant Wavelengths in Donor-Acceptor-Donor Nonlinear Optical Chromophores.

Dr. Beratan is developing theoretical approaches to understand the function of complex molecular and macromolecular systems, including: the molecular underpinnings of energy harvesting and charge transport in biology; the mechanism of solar energy capture and conversion in man-made structures; the nature of charge conductivity in naturally occurring nucleic acids and in synthetic constructs, including the photochemical repair of damaged DNA in extremophiles; CH bond activation by copper oxygenase enzymes; the flow of charge in bacterial appendages on the micrometer length scale; the theoretical foundations for inverse molecular design - the property driven discovery of chemical structures with optimal properties; the exploitation of molecular diversity in the mapping of molecular and materials "space"; the use of infra-red excitation to manipulate electron transport through molecules; the optical signatures of molecular chirality and the influence of chirality on charge transport. Prof. Beratan is affiliated with the Departments of Chemistry, Biochemistry, Physics, as well as Duke's programs in Computational Biology and Bioinformatics, Structural Biology and Biophysics, Nanosciences, and Phononics.  

Our research involves the synthesis of compounds, supermolecular assemblies, nano-scale objects, and electronic materials with unusual ground-and excited-state characteristics, and interrogating these structures using state-of-the-art transient optical, spectroscopic, photophysical, and electrochemical methods. Research activities span physical inorganic chemistry, physical organic chemistry, synthetic chemistry, bioinorganic chemistry, spectroscopy, photophysics, excited-state dynamics, spintronics, and imaging. My laboratory: (i) designs chromophores and supermolecules that display exceptional opto-electronic properties and elucidates their excited-state dynamics, (ii) engineers highly conjugated molecular structures for optical limiting, specialized emission, and high charge mobility, (iii) designs conjugated materials and hybrid molecular-nanoscale structures for energy conversion reactions, (iv) develops molecular wires that propagate spin-polarized currents, (v) fabricates emissive nanoscale structures for in vivo optical imaging, (vi) engineers de novo transition metal cofactor-binding proteins that test light-driven biological energy transducing mechanisms and realize opto-electronic functionalities not found in nature, and (vii) designs and interrogates complex molecular and nanoscale assemblies in which ultrafast energy and charge migration reactions are controlled by quantum coherence effects.