Lorentz-Lorenz coefficient, critical point constants, and coexistence curve of 1,1-difluoroethylene
Bibliographic record
Abstract
We report measurements of the Lorentz-Lorenz coefficient density dependence $\mathcal{L}(\ensuremath{\rho})$, the critical temperature ${T}_{\mathrm{C}}$, and the critical density ${\ensuremath{\rho}}_{\mathrm{C}}$ of the fluid 1,1-difluoroethylene $({\mathrm{H}}_{2}{\mathrm{C}}_{2}{\mathrm{F}}_{2})$. Lorentz-Lorenz coefficient data were obtained by measuring refractive index $n$, and density $\ensuremath{\rho}$ of the same fluid sample independently of one another. Accurate determination of the Lorentz-Lorenz coefficient is necessary for the transformation of refractive index data into density data from optics-based experiments on critical phenomena of fluid systems done with different apparatuses, with which independent measurement of $n$ and $\ensuremath{\rho}$ is not possible. Measurements were made along the coexistence curve of the fluid and span the density range 0.01 to $0.80\phantom{\rule{0.3em}{0ex}}\mathrm{g}\phantom{\rule{0.2em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}3}$. The Lorentz-Lorenz coefficient results show a stronger density dependence along the coexistence curve than previously observed in other fluids, with a monotonic decrease from a density of about $0.2\phantom{\rule{0.3em}{0ex}}\mathrm{g}\phantom{\rule{0.2em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}3}$ onward, and an overall variation of about 2.5% in the density range studied. No anomaly in the Lorentz-Lorenz function was observed near the critical density. The critical temperature is measured at ${T}_{C}=(302.964\ifmmode\pm\else\textpm\fi{}0.002)\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ (29.814 \ifmmode^\circ\else\textdegree\fi{}C) and the measured critical density is ${\ensuremath{\rho}}_{\mathrm{C}}=(0.4195\ifmmode\pm\else\textpm\fi{}0.0018)\phantom{\rule{0.3em}{0ex}}\mathrm{g}\phantom{\rule{0.2em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}3}$.
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 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| 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".