The electronic spectrum and photodissociation of dinitrogen tetroxide (N2O4): Multireference configuration interaction studies
Bibliographic record
Abstract
Multireference configuration interaction (MRCI) calculations were performed for vertical excitation energies and potential curves of N(2)O(4) in D(2h) symmetry using the TZVPP basis set with diffuse functions on the nitrogens. The strong absorption of N(2)O(4) around 185 nm is assigned to the transition from the ground state to 1 (1)B(1u) (σ(O)→σ(∗) (N-N)) rather than 1 (1)B(2u) (π(O)→π(∗) (NO(2) ),n→σ(∗) (N-N)), as previously assumed. (N(2)O(4) is placed in the yz-plane, with N-N along z.) Transition to 1 (1)B(1u) is calculated to have an oscillator strength f=0.71 and is z-polarized, in agreement with the experimental observations. Another state, 2 (1)B(2u), lies close by, however, at a much lower f-value. The weak absorption around 340 nm is assigned to 1 (1)B(3u). Excitation to 1 (1)B(2u) is calculated at 227 nm. There is no clear assignment of a state for the observed shoulder around 260 nm. TD-DFT (time-dependent density functional theory) vertical excitation energies are close to MRCI values. MRCI singlet and triplet potential curves for the dissociation N(2)O(4)→2NO(2), combined with a table of NO(2) states correlating with those of N(2)O(4), indicate possible products of photodissociation at various wavelengths. The extensive literature on the photodissociation of N(2)O(4) is reviewed. DFT geometry optimizations have been performed on low-lying singlet and triplet states.
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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 | 0.000 |
| 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 | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.006 | 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".