Photochemistry studied with <i>ab initio</i> orbital‐correlation and state‐correlation plots: Classic cyclobutene ring opening, and the reaction of N<sub>2</sub> with photoexcited O<sub>2</sub>
Bibliographic record
Abstract
Pericyclic reaction theory arose from ideas presented in 1965, based on orbital-energy correlation diagrams (Woodward and Hoffmann) and state-energy correlation diagrams (Longuet-Higgins and Abrahamson). Here we have used ab initio complete-active-space self-consistent field (CASSCF) calculations to generate such diagrams. First we present diagrams for the classic case of cyclobutene ring opening, to demonstrate agreement between the CASSCF results and the classic diagrams of both Woodward/Hoffmann and Longuet-Higgins/Abrahamson. Then we present diagrams for the more difficult cases of N(2) + photoexcited O(2), to produce either 2 NO or NNO + O. These N(2) + O(2) cases feature significant electron reorganization, for which elementary pencil-and-paper diagrams are less accurate. Finally, the benefits and limitations of such diagrams for predicting photochemistry are briefly discussed.
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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 | 0.000 | 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 | 0.001 |
| 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 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".