Deuterium and Carbon-13 NMR Study of a Banana Mesogen: Molecular Structure and Order
Bibliographic record
Abstract
The orientational order and the molecular structure of the banana mesogen 4-chloro-1,3-phenylene bis{4,4‘-(11-undecenyloxy)benzoyloxy}benzoate have been studied in its nematic phase by means of 2 H and 13 C NMR. A detailed discussion of orientational order parameters for either the entire molecular core or the selectively deuterated fragments, and geometrical features concerning the rigid core of the molecule is given. In particular, the angles θ i between the para axis of the aromatic ring and the long molecular axis for each lateral wing are estimated. Quantum chemical calculations on the rigid core made by the central five aromatic rings, employing the B3LYP density functional method, support the molecular structure derived from the NMR results. This study shows how important is the comparison between 2 H and 13 C NMR to better understand the real structure of banana-shaped compounds in their mesophases and further sheds light on the open question about chirality or achirality of banana molecules.
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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".