Tuning Optical Properties and Enhancing Solid-State Emission of Poly(thiophene)s by Molecular Control: A Postfunctionalization Approach
Bibliographic record
Abstract
Postfunctionalization of poly(3-hexylthiophene) (P3HT) enables the systematic study of electronic and steric effects of various functional groups on the optical and photophysical properties of 3,4-disubstituted poly(thiophene)s. In solution, these 3,4-disubstituted poly(thiophene)s exhibit a lower fluorescence yield (Φ fl ) than P3HT. In the solid state, bromo, chloro, and formyl groups increase Φ fl, whereas nitro groups completely quench fluorescence. Phenyl, p -tolyl, 2- and 4-methoxyphenyl, 2-thienyl, biphenyl, and 1-naphthyl substituents increase the solid-state fluorescence of P3HT by a factor of 2−3 as a result of steric interactions that force the aromatic substituents perpendicular to the main chain. An extensive enhancement in the solid-state Φ fl, 12 times greater than that of P3HT, is observed for polymers containing ortho -alkylphenyl or 2-(3-alkyl)thienyl groups, because of additional steric interactions between methyl or α-methylene hydrogens on the phenyl or thienyl substituents and main-chain thienyl groups. These interactions further increase the planarity of the polymer backbone and lead to an enlargement of the interplanar distance. Partial substitution of P3HT with o -tolyl groups affords polymer films with a solid-state Φ fl of up to 22%.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".