Solid-State <sup>51</sup>V NMR Investigation of the Intercalation of Alkylamines into Layered α-Vanadyl Phosphate
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
The intercalation behavior of layered alpha-phase vanadyl phosphate, alpha-VOPO(4).2H(2)O (alpha-VP), with alkylamine was investigated by (51)V solid-state NMR in combination with powder XRD. The XRD results show that the amines form bimolecular layers upon intercalation. For the intercalation with short chain amines (propylamine, pentylamine, and hexylamine), the C-C chain of the amines is tilted with respect to the inorganic basal plane. The amines with a longer alkyl chain (dodecylamine and hexadecylamine) tend to adopt an orientation where the C-C chain direction is perpendicular to the VP layer. For the amine with eight carbon atoms (octylamine), the intercalation results in two coexisting phases with different chain orientations. (51)V solid-state NMR was used to directly probe the effect of intercalation on the metal center environments. Both (51)V magic-angle spinning and static spectra of alpha-VP intercalated with different amines were obtained at different magnetic fields, and they are sensitive to intercalation. The intercalation induces the (51)V isotropic chemical shift to move toward deshielded direction. (51)V chemical shielding parameters such as the span are sensitive to the orientation of the amine chain with respect to the VP basal plane. For the V centers interacting with the amines having a tilted orientation, the (51)V span gradually decreases with increasing alkyl chain length. However, the span of the (51)V atoms interacting with the amines perpendicular to the VP layer is larger and independent of the length of the alkyl chain. The (51)V NMR data indicate that for the alpha-VPs intercalated with long-chain amines, such as dodecylamine and hexadecylamine, the amines can assume both tilted and perpendicular orientations.
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.
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 it