Weakly Coordinating Ligands: Nuclear Quadrupole Coupling Constants and Asymmetry Parameters of Iodocarbons Coordinated to Metal Ions
Bibliographic record
Abstract
NQR (nuclear quadrupole resonance) spectroscopy is potentially one of the best ways of characterizing the bonding of metal cations such as zirconocene cations and Ag + to halogen donor atoms in weakly coordinating anions and neutral ligands such as halocarbons. Known coordination of organoiodine atoms to silver ions was studied by 127 I NQR spectroscopy in [Ag(p-C 6 H 4 I 2 )](PO 2 F 2 ), [Ag(o-C 6 H 4 I 2 )]N0 3 , [Ag(CH 2 I 2 ) 2 ]PF 6 , and the explosive [Ag(CH 2 I 2 )]NO 3 ; a possible case of iodocarbon coordination to a mercury atom in C 5 Cl 5 HgCl ·CH2I2 was also investigated. Both the low-frequency (ca. 300 MHz) and the high-frequency (ca. 500 MHz) NQR signals were detected for each compound, and, for the first time, the quadrupole coupling constants e 2 Qq zz /h and asymmetry parameters η of coordinated organohalogen atoms were obtained. As compared to the free iodocarbons, substantial (4 - 12%) reductions of e 2 Qq zz /h and substantial increases in η (to about 20 - 40%) were found in the iodocarbon complexes of silver, but not of mercury. From approximate theoretical analysis of the data, it appears that the electronic interaction of silver and iodine is quite substantial.
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 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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| 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) | 0.001 | 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 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".