Photoelectron Spectrum and Energetics of the meta-Xylylene Diradical.
Mathias SteglichVictoria B F CustodisAdam J TrevittGabriel da SilvaAndras BodiPatrick HembergerPublished in: Journal of the American Chemical Society (2017)
The meta-xylylene diradical m-C8H8 is a prototypical organic triplet that represents a building block for organic molecule-based magnets and also serves as a model compound for test and refinement of quantum chemical calculations. Flash vacuum pyrolysis of 1,3-bis-iodomethyl-benzene (m-C8H8I2) produces m-C8H8 in gas phase; we used photoelectron spectroscopy to probe the first two electronic states of the radical cation, and resolve the vibrational fine structure of the ground state band. The determined adiabatic ionization energy of m-C8H8 is (7.27 ± 0.01) eV. Heat of formation of the diradical was established measuring C-I bond dissociation thresholds in the precursor cation and utilizing a thermochemical cycle to yield ΔHf,298K = (325 ± 8) kJ mol-1, ca. 10 kJ mol-1 below the previous value.
Keyphrases
- ionic liquid
- energy transfer
- density functional theory
- molecular dynamics
- molecular dynamics simulations
- quantum dots
- water soluble
- high resolution
- air pollution
- single molecule
- monte carlo
- living cells
- heat stress
- heart failure
- sewage sludge
- gas chromatography
- risk assessment
- solid state
- heavy metals
- simultaneous determination
- anaerobic digestion