Solid state complexes of poly(L‐lysine) with metal chlorides from the 1st row of the d‐block
Bibliographic record
Abstract
Abstract Solid state characterization of poly(L‐lysine)hydrobromide was obtained via differential scanning calorimetry, thermogravimetric analysis, optical microscopy and infrared spectroscopy. The glass transition temperature of poly(L‐lysine)hydrobromide is 178°C. This thermal transition has not been reported previously. Poly(L‐lysine)'s T g decreases when complexes are produced with the following divalent transition metal chlorides; cobalt chloride hexahydrate, nickel chloride hexahydrate, copper chloride dihydrate and anhydrous zinc chloride. At 10 mol% salt, nickel, chloride decreases T g by 45°C, and the general trend is Ni 2+ Co 2+ Zn 2+ Cu 2+ . The depression of poly(L‐lysine)'s T g correlates well with ligand field stabilization energies for pseudo‐octahedral and pseudo‐tetrahedral d n complexes (n = 7, 8, 10) from the 1 st row of the d‐block. However, d 9 copper(II) complexes cannot be included in this empirical correlation. Infrared spectroscopic evidence suggests that Co 2+ , Ni 2+ and Zn 2+ coordinate to the carbonyl oxygen in the main chain of the polymer. When transition metal ions coordinate to CO, the network of hydrogen bonded amide groups is disrupted, which lowers the glass transition. The amide I region of the infrared spectrum reveals a hydrogen bonded CO stretch @ 1655 cm −1 that is characteristic of poly(α‐amino acid) random coil conformations, and a metal‐ligand coordinated CO stretch @ 1625 cm −1 in complexes with divalent cobalt, nickel and zinc. The amide II region of the infrared spectrum near 1550 cm −1 is also sensitive to the formation of coordination complexes with these d‐block metal chlorides.
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) | 0.001 | 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 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".