Bonding between the decavanadate polyanion and the interstitial complex in pascoite-family minerals
Bibliographic record
Abstract
ABSTRACT The decavanadate isopolyanion, [V10O28]6–, is a constituent of pascoite-family vanadate minerals and synthetic materials, and both protonated, [HxV10O28](6–x)–, and mixed-valence, [V4+xV5+10–x)O28](6+x)–, varieties have been described. Here we analyze the interaction between the interstitial complex and the decavanadate structural unit using the principle of correspondence of Lewis acidity-basicity. The Lewis base strengths of the decavanadate polyanions vary from 0.054 to 0.154 vu and [V10O28] structures can form from the simple cations Cs+, Rb+, K+, Tl+, and Na+; simple cations with higher Lewis acidities are too acid to form structures. Cations may bond to transformer (H2O) groups to form polyatomic cations that have lower Lewis acidities than the corresponding simple cation. The occurrence of the polyatomic cation {(V5+O2)Al10(OH)20(H2O)18}11+ in caseyite shows the potential for decavanadate phases to incorporate large heteropolycations into their structures. In turn, this suggests that the [V10O28] polyanions may be used to induce co-crystallization of large aqueous polyatomic cations, thus facilitating their structural characterization. There is an inverse relation between the amount of (H2O) in the interstitial complex and the number of bonds between interstitial simple cations and the O2– ions of the vanadate units, and there is a strong correlation between the unit-cell volume per decavanadate unit and the number of (H2O) groups.
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 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".