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In our experiment, a trace amount of an organic molecule (M = 1H-phenalen-1-one, 9-fluorenone, pyridine, or acridine) was seeded into a gas mix consisting of 3% O2 with a rare gas buffer (He or Ar) and then supersonically expanded. We excited the resulting molecular beam with ultraviolet light at either 355 nm (1H-phenalen-1-one, 9-fluorenone, or acridine) or 266 nm (pyridine) and used resonance enhanced multiphoton ionization (REMPI) spectroscopy to probe for formation of O2 in the a 1Δg state, 1O2. For all systems, the REMPI spectra demonstrates that ultraviolet excitation results in formation of 1O2 and the oxygen product is confirmed to be in the ground vibrational state and with an effective rotational temperature below 80 K. We then recorded the velocity map ion image of the 1O2 product. From the ion images we determined the center-of-mass translational energy distribution, P(ET), assuming photodissociation of a bimolecular M-O2 complex. We also report results from electronic structure calculations that allow for a determination of the M-O2 ground state binding energy. We use the complex binding energy, the energy to form 1O2, and the adiabatic triplet energy for each organic molecule to determine the available energy following photodissociation. For dissociation of a bimolecular complex, this available energy may be partitioned into either center-of-mass recoil or internal degrees of freedom of the organic moiety. We use the available energy to generate a Prior distribution, which predicts statistical energy partitioning during dissociation. For low available energies, less than 0.2 eV, we find the statistical prediction is in reasonable agreement with the experimental observations. However, at higher available energies the experimental distribution is biased to lower center-of-mass kinetic energies compared with the statistical prediction, which suggests the complex undergoes vibrational predissociation.
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This content will become publicly available on June 2, 2027
Beyond layer stacking: molecular Ru 2 O 9 dimer correlations in pressure-synthesized Ba 3 NbRu 2 O 9
We report Ba3NbRu2O9, a new 6H hexagonal perovskite with Ru2O9dimers. It shows antiferromagnetic interactions, spin freezing below 15 K, and transport dominated by dimer-based electronic correlations.
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- PAR ID:
- 10696928
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Dalton Transactions
- Volume:
- 55
- Issue:
- 21
- ISSN:
- 1477-9226
- Page Range / eLocation ID:
- 8413 to 8420
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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