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Helal H, Firoz J, Bilbrey JA, Sprueill H, Herman KM, Krell MM, Murray T, Roldan ML, Kraus M, Li A, Das P, Xantheas SS, Choudhury S. Acceleration of Graph Neural Network-Based Prediction Models in Chemistry via Co-Design Optimization on Intelligence Processing Units. J Chem Inf Model 2024; 64:1568-1580. [PMID: 38382011 DOI: 10.1021/acs.jcim.3c01312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
Atomic structure prediction and associated property calculations are the bedrock of chemical physics. Since high-fidelity ab initio modeling techniques for computing the structure and properties can be prohibitively expensive, this motivates the development of machine-learning (ML) models that make these predictions more efficiently. Training graph neural networks over large atomistic databases introduces unique computational challenges, such as the need to process millions of small graphs with variable size and support communication patterns that are distinct from learning over large graphs, such as social networks. We demonstrate a novel hardware-software codesign approach to scale up the training of atomistic graph neural networks (GNN) for structure and property prediction. First, to eliminate redundant computation and memory associated with alternative padding techniques and to improve throughput via minimizing communication, we formulate the effective coalescing of the batches of variable-size atomistic graphs as the bin packing problem and introduce a hardware-agnostic algorithm to pack these batches. In addition, we propose hardware-specific optimizations, including a planner and vectorization for the gather-scatter operations targeted for Graphcore's Intelligence Processing Unit (IPU), as well as model-specific optimizations such as merged communication collectives and optimized softplus. Putting these all together, we demonstrate the effectiveness of the proposed codesign approach by providing an implementation of a well-established atomistic GNN on the Graphcore IPUs. We evaluate the training performance on multiple atomistic graph databases with varying degrees of graph counts, sizes, and sparsity. We demonstrate that such a codesign approach can reduce the training time of atomistic GNNs and can improve their performance by up to 1.5× compared to the baseline implementation of the model on the IPUs. Additionally, we compare our IPU implementation with a Nvidia GPU-based implementation and show that our atomistic GNN implementation on the IPUs can run 1.8× faster on average compared to the execution time on the GPUs.
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Affiliation(s)
- Hatem Helal
- Graphcore, Kett House, Station Rd, Cambridge CB1 2JH, U.K
| | - Jesun Firoz
- Advanced Computing, Mathematics and Data Division, Pacific Northwest National Laboratory, 1100 Dexter Ave N, Seattle, Washington 98109, United States
| | - Jenna A Bilbrey
- Artificial Intelligence and Data Analytics Division, Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Henry Sprueill
- Artificial Intelligence and Data Analytics Division, Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Kristina M Herman
- Department of Chemistry, University of Washington, Seattle, Washington 98185, United States
| | | | - Tom Murray
- Graphcore, Kett House, Station Rd, Cambridge CB1 2JH, U.K
| | | | - Mike Kraus
- Graphcore, Kett House, Station Rd, Cambridge CB1 2JH, U.K
| | - Ang Li
- Advanced Computing, Mathematics and Data Division, Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Payel Das
- IBM Research, Yorktown Heights, New York 10598, United States
| | - Sotiris S Xantheas
- Department of Chemistry, University of Washington, Seattle, Washington 98185, United States
- Advanced Computing, Mathematics and Data Division, Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
| | - Sutanay Choudhury
- Advanced Computing, Mathematics and Data Division, Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, Washington 99352, United States
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Muller SE, Prange MP, Lu Z, Rosenthal WS, Bilbrey JA. An open database of computed bulk ternary transition metal dichalcogenides. Sci Data 2023; 10:336. [PMID: 37253748 DOI: 10.1038/s41597-023-02103-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 03/24/2023] [Indexed: 06/01/2023] Open
Abstract
We present a dataset of structural relaxations of bulk ternary transition metal dichalcogenides (TMDs) computed via plane-wave density functional theory (DFT). We examined combinations of up to two chalcogenides with seven transition metals from groups 4-6 in octahedral (1T) or trigonal prismatic (2H) coordination. The full dataset consists of 672 unique stoichiometries, with a total of 50,337 individual configurations generated during structural relaxation. Our motivations for building this dataset are (1) to develop a training set for the generation of machine and deep learning models and (2) to obtain structural minima over a range of stoichiometries to support future electronic analyses. We provide the dataset as individual VASP xml files as well as all configurations encountered during relaxations collated into an ASE database with the corresponding total energy and atomic forces. In this report, we discuss the dataset in more detail and highlight interesting structural and electronic features of the relaxed structures.
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Affiliation(s)
- Scott E Muller
- Pacific Northwest National Laboratory, Richland, WA, 99352, USA.
| | - Micah P Prange
- Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | - Zexi Lu
- Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | | | - Jenna A Bilbrey
- Pacific Northwest National Laboratory, Richland, WA, 99352, USA
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3
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Sprueill HW, Bilbrey JA, Pang Q, Sushko PV. Active sampling for neural network potentials: Accelerated simulations of shear-induced deformation in Cu-Ni multilayers. J Chem Phys 2023; 158:114103. [PMID: 36948793 DOI: 10.1063/5.0133023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
Abstract
Neural network potentials (NNPs) can greatly accelerate atomistic simulations relative to ab initio methods, allowing one to sample a broader range of structural outcomes and transformation pathways. In this work, we demonstrate an active sampling algorithm that trains an NNP that is able to produce microstructural evolutions with accuracy comparable to those obtained by density functional theory, exemplified during structure optimizations for a model Cu-Ni multilayer system. We then use the NNP, in conjunction with a perturbation scheme, to stochastically sample structural and energetic changes caused by shear-induced deformation, demonstrating the range of possible intermixing and vacancy migration pathways that can be obtained as a result of the speedups provided by the NNP. The code to implement our active learning strategy and NNP-driven stochastic shear simulations is openly available at https://github.com/pnnl/Active-Sampling-for-Atomistic-Potentials.
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Affiliation(s)
- Henry W Sprueill
- National Security Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - Jenna A Bilbrey
- National Security Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - Qin Pang
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - Peter V Sushko
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
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Bilbrey JA, Heindel JP, Schram M, Bandyopadhyay P, Xantheas SS, Choudhury S. A look inside the black box: Using graph-theoretical descriptors to interpret a Continuous-Filter Convolutional Neural Network (CF-CNN) trained on the global and local minimum energy structures of neutral water clusters. J Chem Phys 2020; 153:024302. [DOI: 10.1063/5.0009933] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Jenna A. Bilbrey
- Computing and Analytics Division, Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, Richland, Washington 99352, USA
| | - Joseph P. Heindel
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
| | - Malachi Schram
- Advanced Computing, Mathematics and Data Division, Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, Richland, Washington 99352, USA
| | - Pradipta Bandyopadhyay
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Sotiris S. Xantheas
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
- Advanced Computing, Mathematics and Data Division, Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, Richland, Washington 99352, USA
| | - Sutanay Choudhury
- Advanced Computing, Mathematics and Data Division, Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, Richland, Washington 99352, USA
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Bilbrey JA, Ramirez EF, Brandi-Lozano J, Sivaraman C, Short J, Lewis ID, Barnes BD, Zirkle LG. Improving radiograph analysis throughput through transfer learning and object detection. ACTA ACUST UNITED AC 2020. [DOI: 10.21037/jmai-20-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Bilbrey JA, Marrero CO, Sassi M, Ritzmann AM, Henson NJ, Schram M. Tracking the Chemical Evolution of Iodine Species Using Recurrent Neural Networks. ACS Omega 2020; 5:4588-4594. [PMID: 32175505 PMCID: PMC7066558 DOI: 10.1021/acsomega.9b04104] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 02/14/2020] [Indexed: 06/10/2023]
Abstract
We apply recurrent neural networks (RNNs) to predict the time evolution of the concentration profile of multiple species resulting from a set of interconnected chemical reactions. As a proof of concept of our approach, RNNs were trained on a synthetic dataset generated by solving the kinetic equations of a system of aqueous inorganic iodine reactions that can follow after nuclear reactor accidents. We examine the minimum dataset necessary to obtain accurate predictions and explore the ability of RNNs to interpolate and extrapolate when exposed to previously unseen data. We also investigate the limits of our RNN by evaluating the robustness of the training initialization on our dataset.
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Affiliation(s)
| | - Andrea N. Bootsma
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | | | | | - Steven E. Wheeler
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
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Grubbs JB, Arnold RM, Roy A, Durie K, Bilbrey JA, Gao J, Locklin J. Degradable Polycaprolactone and Polylactide Homopolymer and Block Copolymer Brushes Prepared by Surface-Initiated Polymerization with Triazabicyclodecene and Zirconium Catalysts. Langmuir 2015; 31:10183-10189. [PMID: 26317405 DOI: 10.1021/acs.langmuir.5b02093] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Surface-initiated ring-opening polymerization (SI-ROP) of polycaprolactone (PCL) and polylactide (PLA) polymer brushes with controlled degradation rates were prepared on oxide substrates. PCL brushes were polymerized from hydroxyl-terminated monolayers utilizing triazabicyclodecene (TBD) as the polymerization catalyst. A consistent brush thickness of 40 nm could be achieved with a reproducible unique crystalline morphology. The organocatalyzed PCL brushes were chain extended using lactide in the presence of zirconium n-butoxide to successfully grow PCL/PLA block copolymer (PCL-b-PLA) brushes with a final thickness of 55 nm. The degradation properties of "grafted from" PCL brush and the PCL-b-PLA brush were compared to "grafted to" PCL brushes, and we observed that the brush density plays a major role in degradation kinetics. Solutions of methanol/water at pH 14 were used to better solvate the brushes and increase the kinetics of degradation. This framework enables a control of degradation that allows for the precise removal of these coatings.
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Affiliation(s)
- Joe B Grubbs
- Department of Chemistry, College of Engineering, and the Center for Nanoscale Science and Engineering, University of Georgia , Athens, Georgia 30602, United States
- Meredian Holdings Group - MHG, 140 Industrial Boulevard, Bainbridge, Georgia 39817, United States
| | - Rachelle M Arnold
- Meredian Holdings Group - MHG, 140 Industrial Boulevard, Bainbridge, Georgia 39817, United States
| | - Anandi Roy
- Department of Chemistry, College of Engineering, and the Center for Nanoscale Science and Engineering, University of Georgia , Athens, Georgia 30602, United States
| | - Karson Durie
- Department of Chemistry, College of Engineering, and the Center for Nanoscale Science and Engineering, University of Georgia , Athens, Georgia 30602, United States
| | - Jenna A Bilbrey
- Department of Chemistry, College of Engineering, and the Center for Nanoscale Science and Engineering, University of Georgia , Athens, Georgia 30602, United States
| | - Jing Gao
- Department of Chemistry, College of Engineering, and the Center for Nanoscale Science and Engineering, University of Georgia , Athens, Georgia 30602, United States
| | - Jason Locklin
- Department of Chemistry, College of Engineering, and the Center for Nanoscale Science and Engineering, University of Georgia , Athens, Georgia 30602, United States
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Huddleston NE, Roy A, Bilbrey JA, Zhao Y, Locklin J. Functionalization of Reactive End Groups in Surface-Initiated Kumada Catalyst-Transfer Polycondensation. ACTA ACUST UNITED AC 2015. [DOI: 10.1002/masy.201300126] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- N. Eric Huddleston
- Department of Chemistry and Biochemistry; University of North Georgia; 82 College Circle Dahlonega GA 30597 USA
| | - Anandi Roy
- Department of Physics and Astronomy and the Center for Nanoscale Science and Engineering; University of Georgia; Athens Georgia 30602 USA
| | - Jenna A. Bilbrey
- Department of Physics and Astronomy and the Center for Nanoscale Science and Engineering; University of Georgia; Athens Georgia 30602 USA
| | - Yiping Zhao
- Department of Chemistry; College of Engineering, and the Center for Nanoscale Science and Engineering; University of Georgia; Athens Georgia 30602 USA
| | - Jason Locklin
- Department of Physics and Astronomy and the Center for Nanoscale Science and Engineering; University of Georgia; Athens Georgia 30602 USA
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Roy A, Gao J, Bilbrey JA, Huddleston NE, Locklin J. Rapid electrochemical reduction of Ni(II) generates reactive monolayers for conjugated polymer brushes in one step. Langmuir 2014; 30:10465-10470. [PMID: 25115133 DOI: 10.1021/la502050n] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
This article reports the development of a robust, one-step electrochemical technique to generate surface-bound conjugated polymers. The electrochemical reduction of arene diazonium salts at the surface of a gold electrode is used to generate tethered bromobenzene monolayers quickly. The oxidative addition of reactive Ni(0) across the aryl halide bond is achieved in situ through a concerted electrochemical reduction of Ni(dppp)Cl2. This technique limits the diffusion of Ni(0) species away from the surface and overcomes the need for solution deposition techniques which often require multiple steps that result in a loss of surface coverage. With this electrochemical technique, the formation of the reactive monolayer resulted in a surface coverage of 1.29 × 10(14) molecules/cm(2), which is a 6-fold increase over previously reported results using solution deposition techniques.
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Affiliation(s)
- Anandi Roy
- Department of Chemistry, College of Engineering, and the Center for Nanoscale Science and Engineering, University of Georgia , Athens, Georgia 30602, United States
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Sontag SK, Bilbrey JA, Huddleston NE, Sheppard GR, Allen WD, Locklin J. π-Complexation in Nickel-Catalyzed Cross-Coupling Reactions. J Org Chem 2014; 79:1836-41. [DOI: 10.1021/jo402259z] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- S. Kyle Sontag
- Department of Chemistry, ‡Center for Computational Chemistry,
and §College of Engineering, University of Georgia, Athens, Georgia 30602, United States
| | - Jenna A. Bilbrey
- Department of Chemistry, ‡Center for Computational Chemistry,
and §College of Engineering, University of Georgia, Athens, Georgia 30602, United States
| | - N. Eric Huddleston
- Department of Chemistry, ‡Center for Computational Chemistry,
and §College of Engineering, University of Georgia, Athens, Georgia 30602, United States
| | - Gareth R. Sheppard
- Department of Chemistry, ‡Center for Computational Chemistry,
and §College of Engineering, University of Georgia, Athens, Georgia 30602, United States
| | - Wesley D. Allen
- Department of Chemistry, ‡Center for Computational Chemistry,
and §College of Engineering, University of Georgia, Athens, Georgia 30602, United States
| | - Jason Locklin
- Department of Chemistry, ‡Center for Computational Chemistry,
and §College of Engineering, University of Georgia, Athens, Georgia 30602, United States
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Fries KH, Sheppard GR, Bilbrey JA, Locklin J. Tuning chelating groups and comonomers in spiropyran-containing copolymer thin films for color-specific metal ion binding. Polym Chem 2014. [DOI: 10.1039/c3py01296d] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Affiliation(s)
- Jenna A. Bilbrey
- Department
of Chemistry and Center for Computational Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Arianna H. Kazez
- Department
of Chemistry and Center for Computational Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Jason Locklin
- Department
of Chemistry and College of Engineering, University of Georgia, Athens, Georgia 30602, United States
| | - Wesley D. Allen
- Department
of Chemistry and Center for Computational Chemistry, University of Georgia, Athens, Georgia 30602, United States
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Affiliation(s)
- Evan M. White
- Department of Chemistry and College of Engineering; University of Georgia; 220 Riverbend Road, Riverbend Research South Athens Georgia 30602
| | - Jeremy Yatvin
- Department of Chemistry and College of Engineering; University of Georgia; 220 Riverbend Road, Riverbend Research South Athens Georgia 30602
| | - Joe B. Grubbs
- Department of Chemistry and College of Engineering; University of Georgia; 220 Riverbend Road, Riverbend Research South Athens Georgia 30602
| | - Jenna A. Bilbrey
- Department of Chemistry and College of Engineering; University of Georgia; 220 Riverbend Road, Riverbend Research South Athens Georgia 30602
| | - Jason Locklin
- Department of Chemistry and College of Engineering; University of Georgia; 220 Riverbend Road, Riverbend Research South Athens Georgia 30602
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Bilbrey JA, Kazez AH, Locklin J, Allen WD. Exact ligand cone angles. J Comput Chem 2013; 34:1189-97. [DOI: 10.1002/jcc.23217] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 12/05/2012] [Accepted: 12/07/2012] [Indexed: 11/11/2022]
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Huddleston NE, Sontag SK, Bilbrey JA, Sheppard GR, Locklin J. Palladium-Mediated Surface-Initiated Kumada Catalyst Polycondensation: A Facile Route Towards Oriented Conjugated Polymers. Macromol Rapid Commun 2012; 33:2115-20. [DOI: 10.1002/marc.201200472] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 08/08/2012] [Indexed: 11/07/2022]
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Bilbrey JA, Sontag SK, Huddleston NE, Allen WD, Locklin J. On the Role of Disproportionation Energy in Kumada Catalyst-Transfer Polycondensation. ACS Macro Lett 2012; 1:995-1000. [PMID: 35607024 DOI: 10.1021/mz3002929] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Kumada catalyst-transfer polycondensation (KCTP) is an effective method for the controlled polymerization of conjugated polymers. Nevertheless, side reactions leading to early termination and unwanted chain coupling cause deviations from the target molecular weight, along with increasing polydispersity and end group variation. The departure from the KCTP cycle stems from a disproportionation reaction that leads to experimentally observed side products. The disproportionation energies for a series of nickel-based initiators containing bidentate phosphino attendant ligands were computed using density functional theory at the B3LYP/DZP level. The initiator was found to be less favorable toward disproportionation by 0.5 kcal mol-1 when ligated by 1,3-bis(diphenylphosphino)propane (dppp) rather than 1,2-bis(diphenylphosphino)ethane (dppe). Trends in disproportionation energy (Edisp) with a variety of bidentate phosphine ligands match experimental observations of decreased polymerization control. Theoretical Edisp values can thus be used to predict the likelihood of disproportionation in cross-coupling reactions and, therefore, aid in catalyst design.
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Affiliation(s)
- Jenna A. Bilbrey
- Department
of Chemistry , ‡College of Engineering, Center for Nanoscale Science and Engineering, and §Center for Computational
Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - S. Kyle Sontag
- Department
of Chemistry , ‡College of Engineering, Center for Nanoscale Science and Engineering, and §Center for Computational
Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - N. Eric Huddleston
- Department
of Chemistry , ‡College of Engineering, Center for Nanoscale Science and Engineering, and §Center for Computational
Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Wesley D. Allen
- Department
of Chemistry , ‡College of Engineering, Center for Nanoscale Science and Engineering, and §Center for Computational
Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Jason Locklin
- Department
of Chemistry , ‡College of Engineering, Center for Nanoscale Science and Engineering, and §Center for Computational
Chemistry, University of Georgia, Athens, Georgia 30602, United States
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