Unimolecular Reactions of Proton-Bound Cluster Ions: Competition between Dissociation and Isomerization in the Ethanol−Acetonitrile Dimer
Bibliographic record
Abstract
The proton-bound dimer of acetonitrile and ethanol, (CH 3 CN)(CH 3 CH 2 OH)H +, exhibits three unimolecular reactions on the microsecond time scale: two simple bond cleavage reactions to form CH 3 CNH + + CH 3 CH 2 OH and CH 3 CH 2 OH 2 + + CH 3 CN, and the loss of water to form CH 3 CNCH 2 CH 3 + . The latter process is preceded by the isomerization of the proton-bound dimer to a second isomer, (CH 3 CNCH 2 CH 3 )(H 2 O) + . The competition between the simple dissociation reactions and the isomerization reaction was modeled with ab initio calculations and RRKM theory to obtain relative energies for the reaction surface. The 0 K binding energy of the (CH 3 CN)(CH 3 CH 2 OH)H + complex was calculated to be 152 kJ mol -1 at the G2(MP2,SVP) level of theory (relative to the dissociation products CH 3 CNH + and CH 3 CH 2 OH). The isomerization barrier for the proton-bound dimer was estimated to be 22 kJ mol -1 lower than CH 3 CNH + + CH 3 CH 2 OH. The greater polarizability of the ethyl group is believed to stabilize this transition structure over that found for the (CH 3 CN)(CH 3 OH)H + ion (which was previously estimated to lie 6 kJ mol -1 below CH 3 CNH + and CH 3 OH).
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 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 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".