The dynamics of substituted benzoate anions undergoing counterion condensation in lamellar phase dispersions
Bibliographic record
Abstract
We have studied the interaction of three ortho-substituted benzoate anions (2-ethylbenzoate, 2-chlorobenzoate, and 2-hydroxybenzoate) and three para-substituted benzoate anions (4-ethylbenzoate, 4-chlorobenzoate, and 4-hydroxybenzoate) with lamellar phase dispersions of the di-chain cationic surfactants 2,3-diheptadecyl ester ethoxypropyl-1,1,1-trimethyl-ammonium chloride (DHTAC) and dioctadecyl-dimethyl-ammonium chloride (DODMAC) using avoided level crossing muon spin resonance (ALC-μSR) spectroscopy. Highly polarized spin probes were produced in situ by the addition of muonium to the aromatic anions, and the muon and methylene proton hyperfine coupling constants (hfccs) of these radical anions were determined from the Δ1 and Δ0 resonance fields in the ALC-μSR spectra. The motionally averaged dipolar muon hfccs, |Dμ‖|, were determined from the width and amplitude of the Δ1 and Δ0 resonances and used to estimate the extent of reorientational motion. The results are consistent with the counterions being electrostatically trapped near the oil/water interface of the surfactant bilayer and undergoing large amplitude anisotropic motion. This motion is generally more restricted in DODMAC bilayers compared with DHTAC, which is likely related to the relative flexibility of the headgroups to which the counterions are loosely bound. The motion of the ortho isomers is generally more restricted than the para isomers, while there is no obvious trend regarding the ethyl, chloro, and hydroxy substituents.
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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".