Deformation of an inner valence molecular orbital in ethanol by an intense laser field

Valence molecular orbitals play a crucial role in chemical reactions. Here, we reveal that an intense laser field deforms an inner valence orbital (10a′) in the ethanol molecule. We measure the recoil-frame photoelectron angular distribution (RFPAD), which corresponds to the orientation dependence of the ionization probability of the orbital, using photoelectron-photoion coincidence momentum imaging with a circularly polarized laser pulse. Ab initio simulations show that the orbital deformation depends strongly on the laser field direction and that the measured RFPAD cannot be reproduced without taking the orbital deformation into account. Our findings suggest that the laser-induced orbital deformation occurs before electron emission on a suboptical cycle time scale.

The nature of chemical bond in trioxide Mi-UO3

Low-energy X-ray photoelectron and conversion electron spectra from uranium trioxide were measured, and calculations were done for the [UO2O4]-6 (D4b) cluster which reflects the structure of uranium close environment in MI-UO3 in the non-relativistic and relativistic Xa-DVM approximation. This enabled a satisfactory qualitative and in some cases quantitative agreement between the experimental and theoretical data, and interpretation of such spectra. Despite the traditional opinion that before participation in the chemical binding, the U5f electrons could be promoted to the higher (for example - U6d) levels, it was theoretically proved and experimentally confirmed that the U5f electrons (about two U5f electrons) are able to participate directly in the chemical bond formation in uranium trioxide. The filled U5f states proved to be localized in the outer valence molecular orbitals energy range 4-9 eV, while the vacant U5f states were generally localized in the low-energy range (0-6 eV above zero). It was experimentally shown that U6p electrons not only participate effectively in the inner valence molecular orbital formation but also participate strongly (more than 1 U6p electron) in the formation of die filled outer valence molecular orbitals.