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Abstract. 2014 Electron energy-loss spectroscopy (EELS) and zero-loss electron spectroscopic imaging (ZLESI) in conjunction with spot energy-dispersive X-ray microanalysis (EDX) were applied to the structural and chemical characterization of practical emulsion core (AgBr)-shell (AgBr1-x Ix) tabular microcrystals. The samples were cryocooled to minimize damage under the electron beam. Recorded energy-loss spectra of the crystals in the initial state and after a 2-minute development contained several low intensity bands, which were tentatively assigned to silver and halides, as well as bulk, surface and defect plasmons and interband transitions. Spatially resolved energy-loss spectra of silver specks on extractive carbon replicas of silver halide grains showed the presence of the delayed Ag M4, 5-edge at 400 eV Results of EELS-microanalysis have been confirmed by EDX spot analysis of the same emulsion samples. The improved contrast in the ZLESI mode enabled the detection of dislocation grid and stacking faults on the tabular grains as well as the visualization of the morphology and defect structure of silver filaments formed during development of microcrystals. Zero-loss filtering was also used to obtain high-resolution point diffraction patterns of the crystals with low background, containing extra reflections at commensurate positions in between the Bragg reflections probably due to a number of defects in the shell region.

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Complex investigations are made of nuclear magnetic resonance of protons and fluorine on the Si02 surface, thermo-and photodesorption of water and hydrogen from the surfaces of silicon and silicon dioxide, and also changes in the electrophysical parameters of the real silicon surface in the process of hydrogen photodesorption. Fluorination is found to lead to a considerable strengthening of the bonds of the water molecules with the coordination-unsaturated silicon atoms and also to protonization of the adsorbed H,O molecules. It is shown that strongly protonized coordination-bound molecules of water are the main source of hydrogen on the fluorinated surfaces.Ways of controlling the proton-donor properties of the surface are discussed. A dissociation mechanism is proposed of the H,O molecules on the semiconductor surface when exposed t o lowenergy light quanta.

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