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The TiLα, FeLα and OKα ultrasoft X-ray emission bands obtained in experiment reflect, respectively, the energy distribution of mainly the Ti3d, Fe3d and O2p electronic states in Ti4Fe2O compound, which is an efficient hydrogen absorber for energy cells. Full and partial densities of electronic states for all atoms constituting the indicated oxide were calculated by a modified method of associated plane waves (APW) using the WIEN2k software package. The APW calculation data for Ti4Fe2O compound as well as superposition of TiLα, FeLα and OKα ultrasoft X-ray emission bands on a single energy scale indicate that O2p states in the oxide are localized mainly near the bottom of the valence band, the major contribution near the ceiling of the valence band belonging to Fe3d and Ti3d states. According to the APW calculation, the major contribution to the bottom of Ti4Fe2O conduction band is made by Fe3d* and Ti3d* states. The APW data for Ti4Fe2O are supported by the cluster calculation performed for this compound using a FEFF82 software package.

Using poly(vinylidene fluoride) (PVDF) carbonization at 750° C in fine-particle silica and its mixtures with graphite, we have prepared carbon-loaded porous composites which offer benzene absorption from 0.90 to 1.52 ml/g, compressive strength of 6 MPa, and Brinell hardness of up to 18 MPa. We observed the formation of various nanostructures (spheres, spherical segments, and layered platelets) and sizes (several to hundred nanometers). X-ray photoelectron and energy dispersive x-ray spectroscopy data indicate the presence of C-C, C =C, CO, COO, and CHF groups on the carbon surface. X-ray emission spectroscopy data show that the silica matrix composite prepared via PVDF carbonization contains small carbon clusters weakly bonded to the matrix. The silica/graphite matrix composite contains multilayer carbon films strongly bonded to the matrix. The OK α spectra of both composites are similar to the spectrum of pure SiO2.