Delayed Dissociation of Photoexcited Porphyrin Cations in a Storage Ring: Determination of Triplet Quantum Yields
Bibliographic record
Abstract
A technique is described wherein substituent-dependent excited-state properties of gas-phase porphyrins can be accurately quantified. Dissociation lifetimes of photoexcited porphyrin cations were measured in an electrostatic ion storage ring. From these data, upper limits for the triplet quantum yield of the following protonated porphyrins were obtained: protoporphyrin IX (0.63 +/- 0.04), tetraphenylporphyrin (0.73 +/- 0.03), tetra(p-methylphenyl)porphyrin (0.75 +/- 0.03), and tetra(p-cyanophenyl)porphyrin (0.71 +/- 0.03). The values compare well with those for porphyrins in solution.
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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 | 0.001 |
| 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 | 0.001 |
| 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; 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".