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Full-Text Articles in Engineering
Tunable Electronic Structure Via Dna-Templated Heteroaggregates Of Two Distinct Cyanine Dyes, Jonathan S. Huff, Matthew S. Barclay, Azhad U. Chowdhury, Lance K. Patten, Simon K. Roy, Aaron Sup, Austin Biaggne, Lan Li, Jeunghoon Lee, Paul H. Davis, Bernard Yurke, William B. Knowlton, Daniel B. Turner, Ryan D. Pensack
Tunable Electronic Structure Via Dna-Templated Heteroaggregates Of Two Distinct Cyanine Dyes, Jonathan S. Huff, Matthew S. Barclay, Azhad U. Chowdhury, Lance K. Patten, Simon K. Roy, Aaron Sup, Austin Biaggne, Lan Li, Jeunghoon Lee, Paul H. Davis, Bernard Yurke, William B. Knowlton, Daniel B. Turner, Ryan D. Pensack
Materials Science and Engineering Faculty Publications and Presentations
Molecular excitons are useful for applications in light harvesting, organic optoelectronics, and nanoscale computing. Electronic energy transfer (EET) is a process central to the function of devices based on molecular excitons. Achieving EET with a high quantum efficiency is a common obstacle to excitonic devices, often owing to the lack of donor and acceptor molecules that exhibit favorable spectral overlap. EET quantum efficiencies may be substantially improved through the use of heteroaggregates─aggregates of chemically distinct dyes─rather than individual dyes as energy relay units. However, controlling the assembly of heteroaggregates remains a significant challenge. Here, we use DNA Holliday junctions to …
Molecular Dynamics Simulations Of Cyanine Dimers Attached To Dna Holliday Junctions, Austin Biaggne, Young C. Kim, Joseph S. Melinger, William B. Knowlton, Bernard Yurke, Lan Li
Molecular Dynamics Simulations Of Cyanine Dimers Attached To Dna Holliday Junctions, Austin Biaggne, Young C. Kim, Joseph S. Melinger, William B. Knowlton, Bernard Yurke, Lan Li
Materials Science and Engineering Faculty Publications and Presentations
Dye aggregates and their excitonic properties are of interest for their applications to organic photovoltaics, non-linear optics, and quantum information systems. DNA scaffolding has been shown to be effective at promoting the aggregation of dyes in a controllable manner. Specifically, isolated DNA Holliday junctions have been used to achieve strongly coupled cyanine dye dimers. However, the structural properties of the dimers and the DNA, as well as the role of Holliday junction isomerization are not fully understood. To study the dynamics of cyanine dimers in DNA, molecular dynamics simulations were carried out for adjacent and transverse dimers attached to Holliday …
Oblique Packing And Tunable Excitonic Coupling In Dna-Templated Squaraine Rotaxane Dimer Aggregates, Matthew S. Barclay, Christopher K. Wilson, Simon K. Roy, Olga A. Mass, Azhad U. Chowdhury, Jonathan S. Huff, Daniel B. Turner, Paul H. Davis, Bernard Yurke, William B. Knowlton, Jeunghoon Lee, Ryan D. Pensack
Oblique Packing And Tunable Excitonic Coupling In Dna-Templated Squaraine Rotaxane Dimer Aggregates, Matthew S. Barclay, Christopher K. Wilson, Simon K. Roy, Olga A. Mass, Azhad U. Chowdhury, Jonathan S. Huff, Daniel B. Turner, Paul H. Davis, Bernard Yurke, William B. Knowlton, Jeunghoon Lee, Ryan D. Pensack
Materials Science and Engineering Faculty Publications and Presentations
When molecules are aggregated such that their excited states form delocalized excitons, their spatial arrangement, or packing, can be coarsely controlled by templating and finely controlled by chemical substitution; however, challenges remain in controlling their packing on intermediate length scales. Here, we use an approach based on mechanically interlocked molecules to promote an elusive oblique packing arrangement in a series of three squaraine rotaxane dimers. We template the squaraine rotaxane dimers using DNA and observe two excitonically split bands of near-equal intensity in their absorption spectra – a distinct signature of oblique packing, validated by theoretical modeling of the experimental …
Characterizing Mode Anharmonicity And Huang–Rhys Factors Using Models Of Femtosecond Coherence Spectra, Matthew S. Barclay, Jonathan S. Huff, Ryan D. Pensack, Paul H. Davis, William B. Knowlton, Bernard Yurke, Jacob C. Dean, Paul C. Arpin, Daniel B. Turner
Characterizing Mode Anharmonicity And Huang–Rhys Factors Using Models Of Femtosecond Coherence Spectra, Matthew S. Barclay, Jonathan S. Huff, Ryan D. Pensack, Paul H. Davis, William B. Knowlton, Bernard Yurke, Jacob C. Dean, Paul C. Arpin, Daniel B. Turner
Materials Science and Engineering Faculty Publications and Presentations
Femtosecond laser pulses readily produce coherent quantum beats in transient–absorption spectra. These oscillatory signals often arise from molecular vibrations and therefore may contain information about the excited-state potential energy surface near the Franck–Condon region. Here, by fitting the measured spectra of two laser dyes to microscopic models of femtosecond coherence spectra (FCS) arising from molecular vibrations, we classify coherent quantum-beat signals as fundamentals or overtones and quantify their Huang–Rhys factors and anharmonicity values. We discuss the extracted Huang–Rhys factors in the context of quantum-chemical computations. This work solidifies the use of FCS for analysis of coherent quantum beats arising from …
Data-Driven And Multiscale Modeling Of Dna-Templated Dye Aggregates, Austin Biaggne, Lawrence Spear, German Barcenas, Maia Ketteridge, William B. Knowlton, Bernard Yurke, Lan Li
Data-Driven And Multiscale Modeling Of Dna-Templated Dye Aggregates, Austin Biaggne, Lawrence Spear, German Barcenas, Maia Ketteridge, William B. Knowlton, Bernard Yurke, Lan Li
Materials Science and Engineering Faculty Publications and Presentations
Dye aggregates are of interest for excitonic applications, including biomedical imaging, organic photovoltaics, and quantum information systems. Dyes with large transition dipole moments (μ) are necessary to optimize coupling within dye aggregates. Extinction coefficients (ε) can be used to determine the μ of dyes, and so dyes with a large ε (>150,000 M−1) should be engineered or identified. However, dye properties leading to a large ε are not fully understood, and low-throughput methods of dye screening, such as experimental measurements or density functional theory (DFT) calculations, can be time-consuming. In order to screen large datasets of molecules …
Tuning Between Quenching And Energy Transfer In Dna-Templated Heterodimer Aggregates, Azhad U. Chowdhury, Jonathan S. Huff, Matthew S. Barclay, Lance K. Patten, Aaron Sup, Natalya Hallstrom, Jeunghoon Lee, Paul H. Davis, Daniel B. Turner, Bernard Yurke, William B. Knowlton, Ryan D. Pensack
Tuning Between Quenching And Energy Transfer In Dna-Templated Heterodimer Aggregates, Azhad U. Chowdhury, Jonathan S. Huff, Matthew S. Barclay, Lance K. Patten, Aaron Sup, Natalya Hallstrom, Jeunghoon Lee, Paul H. Davis, Daniel B. Turner, Bernard Yurke, William B. Knowlton, Ryan D. Pensack
Materials Science and Engineering Faculty Publications and Presentations
Molecular excitons, which propagate spatially via electronic energy transfer, are central to numerous applications including light harvesting, organic optoelectronics, and nanoscale computing; they may also benefit applications such as photothermal therapy and photoacoustic imaging through the local generation of heat via rapid excited-state quenching. Here we show how to tune between energy transfer and quenching for heterodimers of the same pair of cyanine dyes by altering their spatial configuration on a DNA template. We assemble “transverse” and “adjacent” heterodimers of Cy5 and Cy5.5 using DNA Holliday junctions. We find that the transverse heterodimers exhibit optical properties consistent with excitonically interacting …
Exciton Delocalization In A Dna-Templated Organic Semiconductor Dimer Assembly, Xiao Wang, Ruojie Sha, William B. Knowlton, Nadrian C. Seeman, James W. Canary, Bernard Yurke
Exciton Delocalization In A Dna-Templated Organic Semiconductor Dimer Assembly, Xiao Wang, Ruojie Sha, William B. Knowlton, Nadrian C. Seeman, James W. Canary, Bernard Yurke
Materials Science and Engineering Faculty Publications and Presentations
A chiral dimer of an organic semiconductor was assembled from octaniline (octamer of polyaniline) conjugated to DNA. Facile reconfiguration between the monomer and dimer of octaniline–DNA was achieved. The geometry of the dimer and the exciton coupling between octaniline molecules in the assembly was studied both experimentally and theoretically. The octaniline dimer was readily switched between different electronic states by protonic doping and exhibited a Davydov splitting comparable to those previously reported for DNA–dye systems employing dyes with strong transition dipoles. This approach provides a possible platform for studying the fundamental properties of organic semiconductors with DNA-templated assemblies, which serve …