Linda Peteanu

Professor, Chemistry

Education

Ph.D., University of Chicago, 1989
Postdoctoral Fellow, University of California at Berkeley, 1989–1992
Postdoctoral Fellow, University of California at Riverside, 1992–1993

Research

Keywords: Optical properties, morphology, energy and charge transport characteristics of conjugated materials and thin films for molecular electronics; Plasmonic effects on fluorescence and dynamics of conjugated materials; Electronic and optical properties of nanoparticles and nanoclusters for quantum technologies

Our group uses the power of fluorescence microscopy-based methods towards addressing questions in materials science. Our current research follows two main and inter-related threads: using single molecule and thin film imaging methods to investigate the electronic properties of conjugated polymers and nanomaterials and using plasmonics to enhance the emissivity and photostability of conjugated molecules used in solid-state lighting and photovoltaic devices. We supplement studies performed in our own lab with kinetic measurements on ultrafast timescales made at a user facility affiliated with Brookhaven National Laboratories.

In the area of conjugated polymers, we are collaborating with the Noonan and Kowalewski groups to investigate the properties of a new class of helical conjugated polymers based on polyfurans. An important overall goal of these studies, going forward, will be to understand the role that molecular structure and solvent environment can have in determining the magnitude and even the sense of the chirality in these systems. Including and beyond this class of polymers, our interests lie in understanding and optimizing the properties of semi-conducting polymers for energy-efficient lighting applications, lightweight and flexible energy-efficient displays, and for organic-based photovoltaics. Based on our work on the helical polymers thus far, we anticipate that a large number of structures will be synthesized and an even greater number of solvent, temperature, and film casting conditions will need to be explored to optimize properties such as degree of helicity, fluorescence brightness, and conductivity.

Given the large parameter space that is available, these studies may benefit from use of the Cloud lab to speed up the discovery and optimization process. This could involve varying solvent/temperature/concentrations and monitoring spectral properties in solution but would require that the sampling and transfer materials be compatible with organic solvents. Looking forward, optimizing the production of thin films (needed for most applications) could be performed using the Cloud lab if facilities for spin casting solutions to the solid state are incorporated. We are also very interested in establishing collaborations with computational chemists who have an interest in using molecular dynamics to determine how the solvent environment drives conjugated polymer structure and function.

Our work on emissive nanomaterials such as silicon quantum dots and other nanomaterials synthesized by the Jin group has potential uses in biomolecule labeling and in lighting/display applications. We recently proposed exploiting the optical properties of these materials for quantum applications such as ‘single photons on demand’ sources, quantum computing, and potentially as single photon sources for triggering biological events. This project, being done in collaboration with the Jin group and a member of CIT (Elizabeth Dickey, Professor and Department Head, Materials Science and Engineering) was recently funded by the Kaufman Foundation. Looking forward, we imagine creating well-defined assemblies of these emitters using established methods such as the programmable formation of DNA origami structures in order to explore the possibility of coherence, potentially leading to amplification, of single photon emission events.

Projects

Electronic Properties of Molecules used in Organic-Based Lighting

We measure several fundamental electronic properties of molecules such as charge transfer and electronic delocalization using a technique known as Stark spectroscopy. Stark spectroscopy involves applying large electric fields to molecules in films or matrices and analyzing the effects of the field perturbation on the absorption or emission spectrum. We have recently focused on the properties of MEH-PPV and other molecules used to make to organic light emitting diodes (OLED's). Stark spectroscopy reveals the mechanism by which a large applied electric field, such as those present in OLEDs, produces undesirable emission quenching and suggests strategies for minimizing this loss of device efficiency through modifications of the polymer structure.

Emission properties of Single Molecules and Aggregates

Recent years has seen a huge growth in the use of organic conjugated oligomers and polymers in the design of light emitting diodes (OLEDs) and photovoltaic cells. When these molecules are placed in thin films to fabricate devices, they typically form aggregates. These confer several desirable properties for device function such as protection from oxidative damage and enhanced charge transport. However, they also typically shift the wavelength of emission to lower energies and often significantly reduce its intensity. Our group is using microscopy and spectroscopy to investigate the relationships between molecular structure and the brightness and photo-stability of molecules in the solid state, both in isolation (i.e. as single molecules) and as aggregates. We are also developing methods to image aggregation in films at high resolution and to follow the nucleation of aggregates in the solution phase.

Publications

Tailoring Carbon Tails of Ligands on Au₅₂(SR)₃₂ Nanoclusters Enhances the Near-Infrared Photoluminescence Quantum Yield from 3.8 to 18.3%
Yitong Wang, Zhongyu Liu, Abhrojyoti Mazumder, Christopher G. Gianopoulos, Kristin Kirschbaum, Linda A. Peteanu, and Rongchao Jin Journal of the American Chemical Society, November 2023, DOI:10.1021/jacs.3c09846

Cholesterol side groups in Helical Poly(3-alkylesterfurans)
Manami Kawakami, Payton Downey, Linda A. Peteanu, Stefan Bernhard, Kevin Noonan, Polymer Journal, December 2022, DOI:10.1038/s41428-022-00741-w

Investigating the impact of regiochemistry in ester functionalized polyfurans
Anthony J. Varni, Manami Kawakami, Stephanie Kramer, Megan Rice, Steven J. Geib, Linda A. Peteanu, Tomasz Kowalewski, Kevin Noonan, Journal of Polymer Science, September 2021, DOI:10.1002/pol.20210535

Unraveling the Contribution of Residual Monomer to the Emission Spectra of Poly(3-hexylthiophene) Aggregates: Implications for Identifying H- and J-type Coupling
Stephanie Kramer, Jasper Brown, Megan Rice, Linda A. Peteanu, Journal of Physical Chemistry Letters, June 2021, 12(25):5919-5924, DOI:10.1021/acs.jpclett.1c01334

Single- and Bi-Exciton Character in Ligand-Modified Silicon Nanoparticles as Demonstrated via Single Particle Photon Statistics and Plasmonic Effects
Woong Young So, Sikandar Abbas, Qi Li, Rongchao Jin, Linda A. Peteanu, Nanoscale 13(36), June 2021, DOI:10.1039/D1NR00108F

Structural distortion and electron redistribution in dual-emitting gold nanoclusters
Qi Li, Dongming Zhou, Jinsong Chai, Woong Young So, Tong Cai, Mingxing Li, Linda A. Peteanu, Ou Chen, Mircea Cotlet, X. Wendy Gu, Haiming Zhu, Haiming Zhu, Rongchao Jin, Nature Communications 11(1), June 2020, DOI:10.1038/s41467-020-16686-8

A Mono-Cuboctahedral Series of Gold Nanoclusters: Photoluminescence Origin, Large Enhancement, Wide Tunability and Structure-Property Correlation
Qi Li, Meng Zhou, Woong Young So, Jingchun Huang, Mingxing Li, Douglas R. Kauffman, Mircea Cotlet, Tatsuya Higaki, Linda A. Peteanu, Zhengzhong Shao, Rongchao Jin, Journal of the American Chemical Society 141(13), March 2019, DOI:10.1021/jacs.8b13558

Mechanism of Ligand-Controlled Emission in Silicon Nanoparticles
Woong Young So, Qi Li, Christian Legaspi, Brendan Redler, Krystal M. Koe, Rongchao Jin, Linda A. Peteanu, ACS Nano 12(7), May 2018, DOI:10.1021/acsnano.8b03273

Rigidity and Polarity Effects on the Electronic Properties of Two Deep Blue Delayed Fluorescence Emitters
Christian Legaspi, Regan E. Stubbs, Md Wahadoszamen, David J. Yaron, Linda A. Peteanu, Abraham Kemboi, Eric Fossum, Yongli Lu, Qi Zheng, Lewis J. Rothberg, The Journal of Physical Chemistry C 122(22), May 2018, DOI:10.1021/acs.jpcc.7b12025

Eliminating Spurious Zero FRET States in Diffusion-based Single-molecule Confocal Microscopy
Sourav Kumar Dey, John R Pettersson, Andrea Topacio, Subha R. Das, Linda A. Peteanu, Journal of Physical Chemistry Letters 9(9), March 2018, DOI:10.1021/acs.jpclett.8b00362

Detection of Ultralow Concentrations of Non-emissive Conjugated Polymer Aggregates via Fluorescence Correlation Spectroscopy
Eric C. Wu, Regan E. Stubbs, Linda A. Peteanu, Racquel Jemison, Richard D. McCullough, and Jurjen Wildeman
J. Phys. Chem. B 2017, 121 (21), 5413-5421 DOI: 10.1021/acs.jpcb.7b01918

Exciton–Exciton Annihilation as a Probe of Interchain Interactions in PPV–Oligomer Aggregates
Linda A. Peteanu, Sanchari Chowdhury, Jurjen Wildeman, and Matthew Y. Sfeir, J Phys Chem B. 2017 Feb 23;121(7):1707-1714. doi: 10.1021/acs.jpcb.6b11250. Epub 2017 Feb 9

Spectroscopic and MD Study of Dynamic and Structural Heterogeneities in Ionic Liquids
Eric C. Wu, Hyung J. Kim, and Linda A. Peteanu, J . Phys. Chem. B, 2017, 121 (5), pp 1100–1107

Theoretical Investigations on the Roles of Intramolecular Structure Distortion versus Irregular Intermolecular Packing in Optical Spectra of 6T Nanoparticles
Wenqiang Li, Qian Peng, Huili Ma, Jin Wen, Jing Ma, Linda A. Peteanu, Zhigang Shuai, Chemistry of Materials ( IF 9.407 ) 2017-02-03 , DOI: 10.1021/acs.chemmater.6b04210

Mechanism of Photoinduced Metal-Free Atom Transfer Radical Polymerization: Experimental and Computational Studies
Pan, Z., Fang, C., Fantin, M., Malhotra, N., So, W.Y. Peteanu, L. Isse, A. Gennaro, A., Liu, P., and Matyjaszewski, K.,  J. Am. Chem. Soc., 138(7), 2411-2425 (2016)

Dynamic Features of Rod-Shaped Au Nanoclusters
Woong Young So, Anindita Das, Shuxin Wang, Shuo Zhao, Hee Young Byun, Dana Lee, Santosh Kumar, Rongchao Jin, Linda A. Peteanu, Proc. SPIE 9549, Physical Chemistry of Interfaces and Nanomaterials XIV, 95491D (August 20, 2015)

The Role of Local Environment on the Electronic Properties of a Novel Blue-Emitting Donor-Acceptor Compound
Christian M. Legaspi, Regan E. Stubbs, David J. Yaron, Linda A. Peteanu, Abraham Kemboi, Jesse Picker, Eric Fossum, In Proc. SPIE 9923, Physical Chemistry of Interfaces and Nanomaterials XV, 99231K (September 26, 2016)

Modeling Field-Induced Quenching in Poly(p-phenylene vinylene) Polymers and Oligomers 
Legaspi, C.; Peteanu, L. A.; Yaron, D. J. Journal of Physical Chemistry B (invited manuscript) J. Phys. Chem. B, 2015, 119 (24), pp 7625–7634

The Effects of Side-Chain-Induced Disorder on the Emission Spectra and Quantum Yields of Oligothiophene Nanoaggregates: A Combined Experimental and MD-TDDFT Study
Hong, J; Jeon, S.K.; Kim, J. J.; Devi, D.; Chacon-Madrid, K.; Koh, S. M.; Wildeman, J.; Peteanu, L. A.; Ma, J.; J. Phys. Chem. A, 2014, 118 (45), pp 10464–10473. DOI: 10.1021/jp504254a. Publication Date (Web): July 3, 2014

Effects of Solvent Properties on the Spectroscopy and Dynamics of Alkoxy-Substituted PPV Oligomer Aggregates
Woong Young So, Jiyun Hong, Janice J. Kim, Gizelle A. Sherwood, Kelly Chacon-Madrid, James H. Werner, Andrew P. Shreve, and Linda A. Peteanu, Journal of Physical Chemistry B, 116 10504–10513 (2012)

Visualizing Core-Shell Structure in Substituted PPV Oligomer Aggregates Using Fluorescence Lifetime Imaging Microscopy (FLIM)
Peteanu, Linda A.; Sherwood, Gizelle A.; Werner, James H.; Shreve, Andrew P.; Smith, Timothy M.; Wildeman, Jurjen; Journal of Physical Chemistry C, 115 15607–15616 (2011)

Fluorescent DNA Nanotags Featuring Covalently Attached Intercalating Dyes: Synthesis, Antibody Conjugation, and Intracellular Imaging
Stadler, Andrea L.; Delos Santos, Junriz O.; Stensrud, Elizabeth S.; Dembska, Anna; Silva, Gloria L.; Liu, Shengpeng; Shank, Nathaniel I.; Kunttas-Tatli, E.; Sobers, Courtney J.; Gramlich, Philipp M. E.; Carell, Thomas; Peteanu, Linda A.; McCartney, Brooke M.; Armitage, Bruce A.; Bioconjugate Chem. 22 1491–1502 (2011)

Wavelength Dependence of the Fluorescence Quenching Efficiency of Nearby Dyes by Gold Nanoclusters and Nanoparticles: The Roles of Spectral Overlap and Particle Size
Chowdhury, Sanchari; Wu, Zhikun; Jaquins-Gerstl, Andrea; Liu, Shengpeng; Dembska, Anna; Armitage, Bruce A.; Jin, Rongchao; Peteanu, Linda A.; Journal of Physical Chemistry C, 115 20105–20112 (2011)

pH-Responsive Fluorescent Molecular Bottlebrushes Prepared by Atom Transfer Radical Polymerization
Nese, Alper; Lebedeva, Natalia V.; Peteanu, Linda; Sheiko, Sergei, S.; Matyjaszewski, Krzysztof; Macromolecules 44 5905–5910 (2011)

Appointments

Years	Position
2017–2022	Head of Department of Chemistry, Carnegie Mellon University
2011–present	Professor, Carnegie Mellon University
2002–2011	Associate Professor, Carnegie Mellon University
2000–2002	Associate Professor, Carnegie Mellon University
1993–2000	Assistant Professor, Carnegie Mellon University
1992–1993	Post-Doctoral Associate, University of California, Riverside
1989–1992	Post-Doctoral Associate, University of California, Berkeley

Awards and Distinctions

Years	Award
2004–2006	NSF Special Creativity Extension
2000	Fellowship of the Japanese Society for the Promotion of Science
1998	NSF POWRE (Professional Opportunities for Women in Research and Education)
1997	NSF CAREER (Faculty Early Development Program)