Redetermination of (<scp>D</scp>-penicillaminato)lead(II)
Bibliographic record
Abstract
In the title coordination polymer, [Pb(C(5)H(9)NO(2)S)](n) {systematic name: catena-poly[(μ-2-amino-3-methyl-3-sulfido-butano-ato)lead(II)]}, the d-penicillaminate ligand coordin-ates to the metal ion in an N,S,O-tridentate mode. The S atom acts as a bridge to two neighbouring Pb(II) ions, thereby forming a double thiol-ate chain. Moreover, the coordinating carboxyl-ate O atom forms bridges to the Pb(II) ions in the adjacent chain. The overall coordination sphere of the Pb(II) ion can be described as a highly distorted penta-gonal bipyramid with a void in the equatorial plane between the long Pb-S bonds probably occupied by the stereochemically active inert electron pair. The amino H atoms form N-H⋯S and N-H⋯O hydrogen bonds, resulting in a cluster of four complex units, giving rise to an R(4) (4)(16) ring lying in the ab plane. The crystal structure of the title compound has been reported previously [Freeman et al. (1974 ▶). Chem. Soc. Chem. Commun. pp. 366-367] but the atomic coordinates have not been deposited in the Cambridge Structural Database (refcode DPENPB). Additional details of the hydrogen bonding are presented here.
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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 | 0.001 |
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".