Decoherence of entangled protons and attosecond dynamics of C-H bond breaking

In previous neutron Compton scattering experiments on liquid H2O/D2O at room temperature, a decrease of the ratio σH/σD of the H total scattering cross section density σH and the D total scattering cross section density σD has been observed. Furthermore, this decrease exhibits a strong dependence on the H:D composition of the liquid. A striking anomalous decrease of the proton-scattering intensity with respect to that of the carbon nucleus has also been observed in solid fully protonated polystyrene. These results were given a theoretical explanation based on short-lived protonic quantum entanglement. Here, we present the sub-femtosecond dynamics and dissociation of C–H bonds in liquid mixtures of H-acetone (CH3COCH3) and D-acetone (CD3COCD3) with H:D compositions 0.2:0.8, 0.45:0.55, and 0.70:0.30 at T≈298 K. This experiment has shown that (i) the experimental value of σH/σD is strongly decreased with respect to its conventional value (=10.7); (ii) this decrease is strongly dependent on the H:D composition of the liquid H-acetone/D-acetone mixture; and more strikingly (iii) all σH/σD ratios have been found to be significantly smaller than the σH/σD values of the H2O/D2O mixtures. The latter result implies that different dynamics of the decoherence process are involved due to different electronic environments.