The Raman and luminescence spectra of GdVO 4 :Eu 3+ microcrystals have been measured in the pressure range from ambient pressure to 16.4 GPa at room temperature by using a diamond anvil cell. The discontinuities on Raman mode and luminescence intensity and the appearance of new Raman bands and luminescence peaks have provided strong evidence for a phase transition at 7.4 GPa from zircon-type to scheelite-type structure, and the zircon-type and scheelite-type phases coexist over a pressure range of 7.4-16.4 GPa. The scheelite-type phase is retained after release of pressure.

The spin-resolved electronic states and spin polarization of a benzene molecule adsorbed on an Fe(100) surface are investigated using spin-polarized metastable-atom deexcitation spectroscopy (SPMDS) measurements and density functional calculations. The spin asymmetry observed by the SPMDS is found to be negative at the induced π* states close to the Fermi level and positive in molecular orbitals. The opposite spin asymmetry can be explained well by the calculated spin density distributions and plane-averaged density of states on the vacuum side. It is also found that the energy region of the negative spin asymmetry increases with increasing coverage of the benzene molecule. This phenomenon has been discussed in conjunction with the possible multiple adsorption sites, followed by an argument for the site-dependent spin polarization.