Two different three-dimensional hydrogen-bonded framework structures in two hydrated adducts <i>meso</i>-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane–terephthalic acid–water (1/1/4) and (1/1/6)
Bibliographic record
Abstract
Co-crystallization of meso-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, C16H36N4, with terephthalic acid (1,4-benzenedicarboxylic acid), C8H6O4, from ethanol yields the tetrahydrate (C16H36N4).(C8H6O4).(H2O)4 (1), meso-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecaneterephthalic acid-water (1/1/4), while similar co-crystallization from methanol yields the hexahydrate (C16H36N4).(C8H6O4).(H2O)6 (2), meso-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-terephthalic acid-water (1/1/6). Both compounds are salts, [C16H38N4]2+.[C8H4O4]2-. 4H2O (1) and [C16H38N4]2+.[C8H4O4]2-.6H2O (2): in (2) both ionic components lie across centres of inversion and in both salts there are two protons held within the N4 cavity of the cation. In the structure of (1), the cations and anions are linked into chains by means of paired N-H...O hydrogen bonds, and the water molecules are linked into continuous chains by means of O--H...O hydrogen bonds, in which each of the H atoms is independently disordered over two equally populated sites. The water chains link the ionic chains into a continuous three-dimensional framework by means of further O-H...O hydrogen bonds. In (2) the cations and anions are linked by single N--H...O hydrogen bonds, again into chains: at the same time the anions and the water molecules are linked by multiple O-H...O hydrogen bonds into continuous two-dimensional nets, which are linked by the cations, by means of N--H...O hydrogen bonds into a three-dimensional framework, entirely different from that in (1).
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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) | 0.002 | 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".