,
Abaid Ullah,
Menahal Saeed,
Arooj Sajjad,
Rimsha Shareef,
Usman Ghaffar,
Zeshan Sarwa,
Zeeshan Bashir,
Iqra Khaliq
Studying correlating structural properties and performance is critical for the rational advancement of donor materials in organic photovoltaics cells (OPVCs). In this study, thiophene-bridged benzodithiophene (BDT) donors were strategically engineered to probe the impact of π-bridge modulation on electronic structure, optical transitions, and photovoltaic-relevant descriptors using density functional theory (DFT) and time-dependent DFT (TD-DFT). Systematic extension of π-conjugation induces substantial bandgap narrowing from 1.68 to 2.01 eV through enhanced frontier orbital delocalization and reduced HOMO-LUMO separation. This structural modulation produces a pronounced bathochromic shift in absorption maxima up to 815 nm, enabling near-infrared light harvesting. Frontier orbital and density of states analyses reveal intensified intramolecular charge transfer from the electron-rich BDT core to electron-deficient terminals, promoting effective charge separation. Increased dipole moments and oscillator strengths further support improved excitonic dissociation propensity. Theoretical evaluation of open-circuit voltage (Voc) and exciton binding energy (Eb) derived from calculated energy levels suggests favorable donor-acceptor energetic alignment and reduced Coulombic binding. These findings establish π-bridge engineering as a decisive molecular strategy for governing bandgap modulation and charge transport potential in next-generation BDT-based OPVCs systems.
| Published in | International Journal of Computational and Theoretical Chemistry (Volume 14, Issue 2) |
| DOI | 10.11648/j.ijctc.20261402.13 |
| Page(s) | 63-83 |
| Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
| Copyright |
Copyright © The Author(s), 2026. Published by Science Publishing Group |
Benzodithiophene, Π-bridge Engineering, Bandgap Narrowing, Intramolecular Charge Transfer
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APA Style
Javid, M., Ullah, A., Saeed, M., Sajjad, A., Shareef, R., et al. (2026). Correlating Structural Properties and Performance in Thiophene-Bridged Benzodithiophene Donors for Bandgap Narrowing and Efficient Charge Transport in Organic Photovoltaics Cells (OPVCs): Insights from DFT/TD-DFT. International Journal of Computational and Theoretical Chemistry, 14(2), 63-83. https://doi.org/10.11648/j.ijctc.20261402.13
ACS Style
Javid, M.; Ullah, A.; Saeed, M.; Sajjad, A.; Shareef, R., et al. Correlating Structural Properties and Performance in Thiophene-Bridged Benzodithiophene Donors for Bandgap Narrowing and Efficient Charge Transport in Organic Photovoltaics Cells (OPVCs): Insights from DFT/TD-DFT. Int. J. Comput. Theor. Chem. 2026, 14(2), 63-83. doi: 10.11648/j.ijctc.20261402.13
AMA Style
Javid M, Ullah A, Saeed M, Sajjad A, Shareef R, et al. Correlating Structural Properties and Performance in Thiophene-Bridged Benzodithiophene Donors for Bandgap Narrowing and Efficient Charge Transport in Organic Photovoltaics Cells (OPVCs): Insights from DFT/TD-DFT. Int J Comput Theor Chem. 2026;14(2):63-83. doi: 10.11648/j.ijctc.20261402.13
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Download@article{10.11648/j.ijctc.20261402.13,
author = {Muhammad Javid and Abaid Ullah and Menahal Saeed and Arooj Sajjad and Rimsha Shareef and Usman Ghaffar and Zeshan Sarwa and Zeeshan Bashir and Iqra Khaliq},
title = {Correlating Structural Properties and Performance in Thiophene-Bridged Benzodithiophene Donors for Bandgap Narrowing and Efficient Charge Transport in Organic Photovoltaics Cells (OPVCs): Insights from DFT/TD-DFT},
journal = {International Journal of Computational and Theoretical Chemistry},
volume = {14},
number = {2},
pages = {63-83},
doi = {10.11648/j.ijctc.20261402.13},
url = {https://doi.org/10.11648/j.ijctc.20261402.13},
eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijctc.20261402.13},
abstract = {Studying correlating structural properties and performance is critical for the rational advancement of donor materials in organic photovoltaics cells (OPVCs). In this study, thiophene-bridged benzodithiophene (BDT) donors were strategically engineered to probe the impact of π-bridge modulation on electronic structure, optical transitions, and photovoltaic-relevant descriptors using density functional theory (DFT) and time-dependent DFT (TD-DFT). Systematic extension of π-conjugation induces substantial bandgap narrowing from 1.68 to 2.01 eV through enhanced frontier orbital delocalization and reduced HOMO-LUMO separation. This structural modulation produces a pronounced bathochromic shift in absorption maxima up to 815 nm, enabling near-infrared light harvesting. Frontier orbital and density of states analyses reveal intensified intramolecular charge transfer from the electron-rich BDT core to electron-deficient terminals, promoting effective charge separation. Increased dipole moments and oscillator strengths further support improved excitonic dissociation propensity. Theoretical evaluation of open-circuit voltage (Voc) and exciton binding energy (Eb) derived from calculated energy levels suggests favorable donor-acceptor energetic alignment and reduced Coulombic binding. These findings establish π-bridge engineering as a decisive molecular strategy for governing bandgap modulation and charge transport potential in next-generation BDT-based OPVCs systems.},
year = {2026}
}
TY - JOUR T1 - Correlating Structural Properties and Performance in Thiophene-Bridged Benzodithiophene Donors for Bandgap Narrowing and Efficient Charge Transport in Organic Photovoltaics Cells (OPVCs): Insights from DFT/TD-DFT AU - Muhammad Javid AU - Abaid Ullah AU - Menahal Saeed AU - Arooj Sajjad AU - Rimsha Shareef AU - Usman Ghaffar AU - Zeshan Sarwa AU - Zeeshan Bashir AU - Iqra Khaliq Y1 - 2026/10/29 PY - 2026 N1 - https://doi.org/10.11648/j.ijctc.20261402.13 DO - 10.11648/j.ijctc.20261402.13 T2 - International Journal of Computational and Theoretical Chemistry JF - International Journal of Computational and Theoretical Chemistry JO - International Journal of Computational and Theoretical Chemistry SP - 63 EP - 83 PB - Science Publishing Group SN - 2376-7308 UR - https://doi.org/10.11648/j.ijctc.20261402.13 AB - Studying correlating structural properties and performance is critical for the rational advancement of donor materials in organic photovoltaics cells (OPVCs). In this study, thiophene-bridged benzodithiophene (BDT) donors were strategically engineered to probe the impact of π-bridge modulation on electronic structure, optical transitions, and photovoltaic-relevant descriptors using density functional theory (DFT) and time-dependent DFT (TD-DFT). Systematic extension of π-conjugation induces substantial bandgap narrowing from 1.68 to 2.01 eV through enhanced frontier orbital delocalization and reduced HOMO-LUMO separation. This structural modulation produces a pronounced bathochromic shift in absorption maxima up to 815 nm, enabling near-infrared light harvesting. Frontier orbital and density of states analyses reveal intensified intramolecular charge transfer from the electron-rich BDT core to electron-deficient terminals, promoting effective charge separation. Increased dipole moments and oscillator strengths further support improved excitonic dissociation propensity. Theoretical evaluation of open-circuit voltage (Voc) and exciton binding energy (Eb) derived from calculated energy levels suggests favorable donor-acceptor energetic alignment and reduced Coulombic binding. These findings establish π-bridge engineering as a decisive molecular strategy for governing bandgap modulation and charge transport potential in next-generation BDT-based OPVCs systems. VL - 14 IS - 2 ER -
Department of Chemistry, University of Agriculture Faisalabad, Punjab, Pakistan
Department of Chemistry, University of Agriculture Faisalabad, Punjab, Pakistan
Department of Chemistry, Government College University Faisalabad, Punjab, Pakistan
Department of Chemistry, Garrison University Lahore, Punjab, Pakistan
Department of Chemistry, University of Agriculture Faisalabad, Punjab, Pakistan
School of Chemistry and Materials Science, Nanjing Normal University, Jiangsu, China
Department of Chemistry, University of Agriculture Faisalabad, Punjab, Pakistan
Department of Chemistry, University of Agriculture Faisalabad, Punjab, Pakistan
Institute of Chemistry, Khawaja Fareed University of Engineering and Information Technology, Rahim Yar Khan, Pakistan
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