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CdSe is one of the most promising photoelectrochemical materials. A common problem of the CVD of multicomponent systems is obtaining the appropriate stoichiometry in the gas phase. This can be overcome by using single source precursors containing the required elements. This communication reports on an improved precursor of this type. The figure shows an AFM image of a layer of CdSe on silica. Conclusions are drawn about the growth mechanism.

For the first time, solid-gas reaction techniques have been used for the synthesis and processing of thin films of boron nitride. Clear to intensely colored blue BN films were grown on Si(100) substrates by the transformation of borazine (B3N,H,) with a titanium complex as initiator under flowing nitrogen gas. The thickness of the films ranged from 70 to lOOnm, as determined by Rutherford backscattering (RBS) and atomic force microscopy (AFM) analyses. The intensity of the blue color of the thin film can be correlated to its thickness. The composition of the film determined by RBS studies corresponds to the stoichiometric formula B0~49N0,4500,06r and N/B and O/B ratios are found to be 0.92 and 0.12, respectively. Nitrogen contents determined by nuclear reaction analysis agree well with the RBS results. Moreover, Auger electron spectroscopy (AES) measurements show that no titanium is present in the films and confirm the composition determined by RBS studies. X-ray photoelectron spectroscopy (XPS) shows the presence of boron and nitrogen in the blue BN film. Electron spin resonance (ESR) experiments at 293 and 12 K indicate a single broad signal with a g value (g = 2.005) close to that of a free electron. This synthetic approach provides opportunities for the preparation of new thin-film materials and for the fundamental study of solid-gas reactions.

In this paper, we have investigated the structural, elastic, optoelectronic and thermoelectric properties of the new half-Heusler alloys TiXSb (X: Ru, Pt) and Ti 2 RuPtSb 2 double half-Heusler compound, using the full-potential linearized augmented plane wave method. Different approximations for the exchange-correlation functional were performed as generalized gradient approximation + Hubbard potential (GGA + U) and its combination with the modified Becke-Johnson potential. The negative values of the calculated formation energy indicate that these compounds are energetically stable. Both half Heusler alloys are halfmetallic ferromagnetic materials and exhibit an integer magnetic moment of Mt = 1.00 μ B .While, the Ti 2 RuPtSb 2 is a direct semiconductor at center symmetry. The calculations of optical properties revealed that Ti 2 RuPtSb 2 compound exhibits an excellent optical efficiency. The thermoelectric properties such as the Seebeck coefficient (S); electronic thermal conductivity (κ e /τ), power factor (PF), and figure of merit (ZT) have been studied and discussed in detail. Consequently, the investigated compounds were identified as candidate materials for high technological applications.