Crystal structures of μ-oxalato-bis[azido(histamine)copper(II)] and μ-oxalato-bis[(dicyanamido)(histamine)copper(II)]
Bibliographic record
Abstract
The title compounds, μ-oxalato-κ(4) O (1),O (2):O (1'),O (2')-bis-[[4-(2-amino-eth-yl)-1H-imid-azole-κ(2) N (3),N (4)](azido-κN (1))copper(II)], [Cu2(C2O4)(N3)2(C5H9N3)2], (I), and μ-ox-al-ato-κ(4) O (1),O (2):O (1'),O (2')-bis-[[4-(2-amino-eth-yl)-1H-imidazole-κ(2) N (3),N (4)](dicyanamido-κN (1))copper(II)], [Cu2(C2O4)(C2N3)2(C5H9N3)2], (II), are two oxalate-bridged dinuclear copper complexes. Each Cu(II) ion adopts a five-coordinate square-pyramidal coordination sphere where the basal N2O2 plane is formed by two O atoms of the oxalate ligand and two N atoms of a bidentate chelating histamine mol-ecule. The apical coordination site in compound (I) is occupied by a monodentate azide anion through one of its terminal N atoms. The apical coordination site in compound (II) is occupied by a monodentate dicyanamide anion through one of its terminal N atoms. The mol-ecules in both structures are centrosymmetric. In the crystals of compounds (I) and (II), the dinuclear complexes are linked through N-H⋯X and C-H⋯X (X = N, O) hydrogen bonds where the donors are provided by the histamine ligand and the acceptor atoms are provided by the azide, dicyanamide, and oxalate ligands. In compound (I), the coordinatively unsaturated copper ions inter-act with the histamine ligand via a C-H⋯Cu inter-action. The coordinatively unsaturated copper ions in compound (II) inter-act via a weak N⋯Cu inter-action with the dicyanamide ligand of a neighboring mol-ecule. The side chain of the histamine ligand is disordered over three sets of sites in (II).
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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 | 0.002 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.003 | 0.004 |
| Science and technology studies | 0.003 | 0.004 |
| Scholarly communication | 0.000 | 0.002 |
| Open science | 0.003 | 0.003 |
| Research integrity | 0.001 | 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; both teacher heads agree on what is shown here.
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".