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Frescission charged-particle multiplicities, following fusion of ^^^'i6'''''^0Er+^^Si, have been measured. The multipHcities at the lowest bombarding energies limit the statistical model level density parameters. More importantly, the a data restrict the time spent near equilibrium and suggest evaporation occurs predominantly from larger deformations.

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Photoelectron spectroscopy studies of (001) oriented PbTi0.8Zr0.2O3 (PZT) single crystal layers with submicron resolution revealed areas with different Pb 5d binding energies, attributed to the different charge and polarization states of the film surface. Two novel effects are evidenced by using intense synchrotron radiation beam experiments: (i) the progressive increase of a low binding energy component for the Pb core levels (evidenced for both 5d and 4f, on two different measurement setups), which can be attributed to a partial decomposition of the PZT film at its surface and promoting the growth of metallic Pb during the photoemission process, with the eventuality of the progressive formation of areas with downwards ferroelectric polarization; (ii) for films annealed in oxygen under clean conditions (in an ultrahigh vacuum installation) a huge shift of the Pb 5d core levels (by 8-9 eV) towards higher binding energies is attributed to the formation of areas with depleted mobile charge carriers, whose surface density is insufficient to screen the depolarization field. This shift is attenuated progressively with time, as the sample is irradiated with high flux soft X-rays. The formation of these areas with strong internal electric field promotes these films as good candidates for photocatalysis and solar cells, since in the operation of these devices the ability to perform charge separation and to avoid electron-hole recombination is crucial.

The level structure of odd-proton '" Au was studied using the " Yb{' F,4n) reaction. Gammagamrna coincidence, angular distributions and y-y-time measurements were used to establish the energies, spins, parities, and lifetimes for the states in the decay scheme of '"Au. Both prolate and oblate structures have been established. The prolate bands are built on the~h9/2 (o, =+~) and thẽ i &3/2 (cx=~) particle states. An oblate, strongly coupled band built on a 90+10 ns isomeric state is reported for the first time. A second oblate structure built on the A»/~p roton-hole state was established to much higher spin than before. The backbend present in the~i »/2 band has been interpreted as the alignment of a pair of h9/p protons.

The effects of the bonding mechanism and band alignment in a ferroelectric (FE) BaTiO 3 /ferromagnetic La 0.6 Sr 0.4 MnO 3 heterostructure are studied using x-ray photoelectron spectroscopy and first-principles calculations. The band lineup at the interface is determined by a combination of band bending and polarization-induced modification of core-hole screening. A Schottky barrier height for electrons of 1.22 ± 0.17 eV is obtained in the case of downwards FE polarization of the top layer. The symmetry of the bonding states is emphasized by integrating the local density of states ±0.2 eV around the Fermi level, and strong dependence on the FE polarization is found: upwards, polarization stabilizes Ti t 2g (xy) orbitals, while downwards, polarization favors Ti t 2g (yz) symmetry. It is predicted that the abrupt (La,Sr)|TiO 2 interface is magnetoelectrically active, leading to a A-type antiferromagnetic coupling of the first TiO 2 interface layer with the underlying manganite layer through a superexchange mechanism.

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