Version 1
: Received: 11 February 2023 / Approved: 16 February 2023 / Online: 16 February 2023 (04:43:46 CET)
How to cite:
Ayoub, S.; Lagowski, J. The Most Stable Structure of PTB7-Th: DFT Conformational Analysis. Preprints2023, 2023020270. https://doi.org/10.20944/preprints202302.0270.v1.
Ayoub, S.; Lagowski, J. The Most Stable Structure of PTB7-Th: DFT Conformational Analysis. Preprints 2023, 2023020270. https://doi.org/10.20944/preprints202302.0270.v1.
Cite as:
Ayoub, S.; Lagowski, J. The Most Stable Structure of PTB7-Th: DFT Conformational Analysis. Preprints2023, 2023020270. https://doi.org/10.20944/preprints202302.0270.v1.
Ayoub, S.; Lagowski, J. The Most Stable Structure of PTB7-Th: DFT Conformational Analysis. Preprints 2023, 2023020270. https://doi.org/10.20944/preprints202302.0270.v1.
Abstract
PTB7-Th is an important donor copolymer used in construction of many organic devices and other industrial applications. In this work, we investigate the structure and energetics of PTB7-Th. We employ density functional theory (DFT) (B3LYP), dispersion corrected DFT (B3LYP-D3) and long-range corrected DFT (CAM-B3LYP, LC-BLYP, and ωB97xD) to analyze the conformational structures and their corresponding energies to determine the lowest energy state of PTB7-Th. The role of the alkane side chains is carefully investigated. Our findings indicate that, when branched ethylhexyl side chains are present, the lowest energy structure of PTB7-Th has fluorine in the same plane and the same side as the double bonded oxygen in the TT-CF part of the monomer and S-C-C-S dihedral angles along the chain backbone are cis-like having values in the range of 20-30 degrees in most cases. Without these side chains the polymer, not unexpectedly, has many near conformational degeneracies.
Keywords
PTB7-Th; donor polymer; lowest energy structure; alkane side chains; density func-tional theory; dispersion correction; long-range correction
Subject
PHYSICAL SCIENCES, Condensed Matter Physics
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
