Multilayer thin films of sequentially adsorbed polyelectrolytes were utilized as nanoreactors for both metallic (Ag) and semiconductor nanoparticles (PbS). Polyelectrolyte multilayers with a controlled content of free carboxylic acid binding groups were fabricated with weak polyelectrolytes via suitable pH adjustments of the processing solutions. These groups were then used to bind various inorganic ions that were subsequently converted into nanoparticles. Spatial control (at the nanoscale) over the growth of the nanoparticles was achieved via the use of multilayer heterostructures that also contain bilayer blocks that are not able to bind inorganic ions. These “nonbinding” bilayers were fabricated from strong polyacids such as poly(styrene sulfonic acid). TEM imaging of the nanoparticles within the multilayer thin films indicates that the polycation and polyanion layers of these films are highly interpenetrated.

Abstract. Three calibration campaigns of the spectrometer SPI have been performed before launch in order to determine the instrument characteristics, such as the effective detection area, the spectral resolution and the angular resolution. Absolute determination of the effective area has been obtained from simulations and measurements. At 1 MeV, the effective area is 65 cm 2 for a point source on the optical axis, the spectral resolution ∼2.3 keV. The angular resolution is better than 2.5• and the source separation capability about 1• . Some temperature dependant parameters will require permanent in-flight calibration.

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This article is mainly devoted to the modeling and measurement of the absorption and fluorescence angular distributions in polarized light of monoclinic crystals. Up to now theoretical crystal optics were mostly devoted to crystals having a high crystallographic symmetry. In these crystals belonging to the cubic, hexagonal, tetragonal, trigonal or orthorhombic lattice classes, the tensor properties related to the real part of the dielectric permittivity and to its imaginary part can be described in the same frame which orientation does not vary as a function of wavelength. The situation is much more complicated in the case of monoclinic crystals because it is necessary to define a specific frame for each property and each wavelength that are considered. The main features of monoclinic crystal optics are described in detail, followed by a review of monoclinic materials and the consequence of these features on their related optical properties.

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