Rotational viscosity, dynamic phenomena, and dielectric properties in a long-chain liquid crystal: NMR study and theoretical treatment
Bibliographic record
Abstract
The rotational diffusion constants ${D}_{\ensuremath{\perp}}$ and ${D}_{\ensuremath{\parallel}},$ rotational viscosity coefficients ${\ensuremath{\gamma}}_{i} (i=1,2),$ the orientational correlation times ${\ensuremath{\tau}}_{\mathrm{mn}}^{L},$ and the dielectric permittivities for nematic liquid crystals (NLCs) are investigated. ${\ensuremath{\gamma}}_{i}$ are calculated by a combination of existing statistical-mechanical approach (SMA) and NMR relaxation theory, both based on a rotational diffusion model. In the rotational diffusion model, it is assumed that the reorientation of an individual molecule is a stochastic Brownian motion in a certain potential of mean torque. According to the SMA, ${\ensuremath{\gamma}}_{i}$ are found to be a function of temperature, density, rotational diffusion constant for tumbling motions, and the orientational order parameters. The order parameters and rotational diffusion constant are obtained from an analysis of NMR measurements. Reasonable agreement between the calculated and experimental values of ${\ensuremath{\gamma}}_{i}$ for 4-n-octyloxy-${4}^{\ensuremath{'}}$-cyanobiphenyl (8OCB) is obtained. The orientational correlation times, and the longitudinal and transverse components of the real ${\ensuremath{\chi}}_{j}^{\ensuremath{'}}(\ensuremath{\omega})$ and imaginary ${\ensuremath{\chi}}_{j}^{\ensuremath{''}}(\ensuremath{\omega}) (j=\ensuremath{\parallel},\ensuremath{\perp})$ parts of the complex susceptibility tensor for 8OCB molecules in the nematic phase are also obtained.
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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 | 0.001 |
| Scholarly communication | 0.000 | 0.001 |
| 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".