Isomeric Control of Structure and Properties in Tolyl-phenyl-1,2,3,5-dithiadiazolyl Radicals
Bibliographic record
Abstract
An isomeric series of 1,2,3,5-dithiadiazolyl (DTDA) radicals, 4′-( p -tolyl)C 6 H 4 CNSSN ( 1 ), 3′-( p -tolyl)C 6 H 4 CNSSN ( 2 ), and 2′-( p -tolyl)C 6 H 4 CNSSN ( 3 ), were prepared and crystallized by vacuum sublimation. Radical 1 exhibits monotropic polymorphism, crystallizing as three polymorphs ( 1α, 1β, and 1γ ) depending on the sublimation conditions. Each polymorph forms pancake-bonded dimers: 1α adopts a cis-oid dimer conformation, whereas both 1β and 1γ crystallize as trans-cofacial dimers, but with 1β and 1γ adopting different packing motifs. A combination of DSC and VT-PXRD revealed successive transformations 1α → 1β and 1β → 1γ upon heating, reflecting 1γ as the most entropically stable phase. Crystallization of 1 from the molten state is cooling-rate-dependent, affording 1β as the thermodynamic phase on slow cooling. The crystal structure of 2α comprises a mixture of both twisted and trans-cofacial dimer conformations, while in 3α, molecules adopts a trans-antarafacial dimer conformation to accommodate the steric hindrance of the ortho -tolyl group. SQUID magnetometry measurements reveal that 1α, 2α, and 3α are all diamagnetic at low temperature but exhibit an increase in sample paramagnetism on warming. Thermal studies reveal that 2α and 3α melt to form metastable glassy phases. VT EPR studies indicate that glassy 2 largely dimerizes upon cooling, whereas 3 largely retains its paramagnetism in the glassy phase.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| 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) | 0.000 | 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 teacher head, 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".