Spencer M. Yeager

University of Arizona

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Michael A. Anderson

University of Arizona

Bryon W. Larson

National Renewable Energy Laboratory

Erin L. Ratcliff

University of Arizona

Natalie Stingelin

Georgia Institute of Technology

Carlos Silva

Université de Montréal

Kari L. Copeland

Allen University

Sergei Tretiak

Los Alamos National Laboratory

Jeffrey D. Veals

United States Army Combat Capabilities Development Command

Priscilla Babiak

University of Arizona

Henry J. Kantrow

Georgia Institute of Technology

Cooperative Institutions

Georgia Institute of Technology

University of Mississippi

University of Arizona

Imperial College London

Centre National de la Recherche Scientifique

Los Alamos National Laboratory

National Renewable Energy Laboratory

Bridge University

Johannes Gutenberg University Mainz

Laboratoire de Chimie des Polymères Organiques

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Unraveling the differences in disorder between flexible-chain and hairy-rod conjugated polymers

Henry J. Kantrow Spencer M. Yeager Hongmo Li Sergei Tretiak Carlos Silva

Chain (unit)

10.1117/12.3028603

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Absorbance Dataset for ColorLab Demo

Zenodo (CERN European Organization for Nuclear Research) (2022)

Michael A. Anderson Bryon W. Larson Spencer M. Yeager

This dataset contains absorbance data for a blend of the polymer poly[1,3,4-thiadiazole-2,5-diyl(3-octyl-2,5-thiophenediyl)[4,8-bis[(2-butyloctyl)thio]benzo[1,2-b:4, 5-b′]dithiophene-2,6-diyl](4-octyl-2,5-thiophenediyl)] (PBDTS-TDZ, CAS: n.a.) and the non-fullerene molecule 2,2'-((2Z,2'Z)-(((4,4,9,9-tetrakis(4-hexylphenyl)-4,9-dihydro-sindaceno[1,2-b:5,6-b']dithiophene-2,7-diyl)bis(4-((2-ethylhexyl)oxy)thiophene-5,2- diyl))bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1- diylidene))dimalononitrile (IEICO-4F, CAS: 2089044-02-8). The spectra in this dataset were recorded over an approximately 144 hour period to monitor the blend's degradation. It can be used alongside ColorLab, both as a sample dataset to use the with the program and as a template for formatting input data.

Absorbance

10.5281/zenodo.6332945

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ColorLab: Visualizing Color from Absorbance Spectra

Spencer M. Yeager Michael A. Anderson Priscilla Babiak Bryon W. Larson Erin L. Ratcliff

We present here the first public release of ColorLab, a Python-based program that can convert absorbance spectra into color images. It was designed for use with organic photovoltaic (OPV) materials and blends, which represent a myriad of colors based on molecular design and material blending that can exhibit persistent color or evolve over time via degradation or morphology changes. However, ColorLab is not limited to this application, and can generate color images from a single spectrum or an evolving color bar on a time axis from multiple time-stamped spectra. Using internationally defined illuminants, ColorLab can display colors that are representative of a variety of lighting situations, from indoor to outdoor. The development of this program aims to aid with the visualization of semitransparent materials and to connect researchers with designers, through conversion of spectra to color.

Absorbance

RGB color model

Python

10.26434/chemrxiv-2022-g5v90

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MRMP2, CCSD(T), and DFT Calculations of the Isomerization Barriers for the Disrotatory and Conrotatory Isomerizations of 3-Aza-3-ium-dihydrobenzvalene, 3,4-Diaza-3-ium-dihydrobenzvalene, and 3,4-Diaza-diium-dihydrobenzvalene

The Journal of Physical Chemistry A (2017)

Jeffrey D. Veals Kimberley N. Poland William P. Earwood Spencer M. Yeager Kari L. Copeland

The isomerizations of 3-aza-3-ium-dihydrobenzvalene, 3,4-diaza-3-ium-dihydrobenzvalene, and 3,4-diaza-diium-dihydrobenzvalene to their respective cyclic-diene products were studied using electronic structure methods with a multiconfigurational wave function and several single reference methods. Transition states for both the allowed (conrotatory) and forbidden (disrotatory) pathways were located. The conrotatory pathways of each structure all proceed through a cyclic intermediate with a trans double bond in the ring: this trans double bond destroys the aromatic stabilization of the π electrons due to poor orbital overlap between the cis and trans π bonds. The 3,4-diaza-3-ium-dihydrobenzvalene structure has C1 symmetry, and there are four separate allowed and forbidden pathways for this structure. The 3-aza-3-ium-dihydrobenzvalene structure is Cs symmetric, and there are two separate allowed and forbidden pathways for this structure. For 3,4-diaza-3,4-diium-dihydrobenzvalene, there was a single allowed and single forbidden pathway due to the C2v symmetry. The separation of the barrier heights for all three molecules was studied, and we found the difference in activation barriers for the lowest allowed and lowest forbidden pathways in 3,4-diaza-3-ium-dihydrobenzvalene, 3-aza-3-ium-dihydrobenzvalene, and 3,4-diaza-diium-dihydrobenzvalene to be 9.1, 7.4, and 3.7 kcal/mol, respectively. The allowed and forbidden barriers of 3,4-diaza-diium-dihydrobenzvalene were separated by 3.7 kcal/mol, which is considerably less than the 12-15 kcal/mol expected based on the orbital symmetry rules. The addition of the secondary ammonium group tends to shift the conrotatory and disrotatory barriers up in energy (∼12-14 kcal/mol (conrotatory) and 5-10 kcal/mol (disrotatory) per secondary NH2 group) relative to the barriers of dihydrobenzvalene, but there is negligible effect on E,Z to Z,Z isomerization barriers, which remain in the expected range of greater than 4 kcal/mol.

Conrotatory and disrotatory

10.1021/acs.jpca.7b08227

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Absorbance Dataset for ColorLab Demo

Zenodo (CERN European Organization for Nuclear Research) (2022)

Michael A. Anderson Bryon W. Larson Spencer M. Yeager

Absorbance

10.5281/zenodo.6332946

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Citations (1)