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The photodissociation of O3 in the Hartley band has been investigated by high-resolution photofragment translational spectroscopy (PTS). At λdiss=248 nm we determined the quantum yield of the dominant decay channel leading to O2(1Δg)+O(1D) and the fragment vibrational state distribution. The fragment recoil anisotropy (β=1.25±0.15) was found to be independent of the fragment vibrational states. Between λdiss=275 and 295 nm β assumes a value of 1.6±0.2, which exceeds the value expected for a simple impulsive process. Photofragment yield measurements carried out by PTS between 272 and 286 nm revealed a strong fluctuation of the vibrational state distribution with λdiss. Based on the small but distinct structure superimposed on the broad continuum of the Hartley band and the findings of recent 3D wave packet calculations, we propose this fluctuation, a manifestation of wavelength-dependent partial cross sections, to arise predominantly from an interference effect. The latter occurs between the part of the initially prepared wavepacket which propagates directly into the exit channel and a (minor) part which is temporarily trapped by the motion of the bending and symmetric stretching modes in the excited O3 molecule.

The three-body dissociation of 1,3,5-triazine (H 3 C 3 N 3 f 3HCN) has been studied by molecular beam photofragment translational spectroscopy following excitation at 308, 295, 285, 275, 248, and 193 nm. The analysis of the measured translational energy distributions of the HCN photofragments has shown that the dissociation mechanism is not, as previously suggested, a symmetric (or synchronous) three-body process but rather is a two-step concerted process, where concerted refers to correlation between the asymptotic velocity vectors of the three ejected HCN fragments. Furthermore, there is evidence that the initially excited electronic state ( 1 E′′, 1 A 2 ) is deactivated by radiationless processes (internal conversion/intersystem crossing) to a lower electronic and finally dissociative state which is, according to symmetry correlation, the electronic ground state (electronic predissociation).

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We prove that local observables of the set of GHZ operators for particles of spin higher than 1 2 reduce to direct sums of the spin-1 2 operators σ x and σ y and, therefore, no new contradictions with local realism arise by considering them.