[Show abstract][Hide abstract] ABSTRACT: The local atomic structure of the glassy Al(92)U(8) alloy was modelled by the reverse Monte Carlo (RMC) method, fitting x-ray diffraction (XRD) and extended x-ray absorption fine structure (EXAFS) signals. The final structural model was analysed by means of partial pair correlation functions, coordination number distributions and Voronoi tessellation. In our study we found that the most probable atomic separations between Al-Al and U-Al pairs in the glassy Al(92)U(8) alloy are 2.7 Å and 3.1 Å with coordination numbers 11.7 and 17.1, respectively. The Voronoi analysis did not support evidence of the existence of well-defined building blocks directly embedded in the amorphous matrix. The dense-random-packing model seems to be adequate for describing the connection between solvent and solute atoms.
[Show abstract][Hide abstract] ABSTRACT: Germany. As34Se51Ag15 and As 34Se51I15 glasses have been studied with high energy X-ray diffraction, neutron diffraction and extended X-ray absorption spectroscopy at various edges. The experimental data have been modelled simultaneously with the reverse Monte Carlo simulation method. Combination of the three independent measurements allowed the separation of the partial pair correlation functions and estimation of the corresponding coordination numbers. Structure modifications induced by different doping elements are established.
Journal of Optoelectronics and Advanced Materials 09/2007; 9(9):2750. · 0.43 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The structure of sputtered amorphous Ge(2)Sb(2)Te(5) was investigated by high energy x-ray diffraction, neutron diffraction and Ge-, Sb- and Te K-edge EXAFS measurements. The five datasets were modelled simultaneously in the framework of the reverse Monte Carlo simulation technique. It was found that apart from Te-Sb and Te-Ge bonds existing in the crystalline phases, Ge-Ge and Sb-Ge bonding is also significant in sputtered amorphous Ge(2)Sb(2)Te(5). According to our results, all components obey the '8-N' rule.
[Show abstract][Hide abstract] ABSTRACT: The atomic structure of the binary AsSe, ternary (AsSe)(80)Ag-20, (AsSe)(85)I-15 and quaternary (AsSe)(65)(AgI)(35) glasses has been studied with the X-ray and neutron diffraction. The local order was also probed with the extended X-ray absorption fine structure spectroscopy at Ag, As and Se K-edges. All experimental data were modeled simultaneously by the reverse Monte Carlo technique. Analysis of the partial pair distribution functions and their characteristics enabled to retrace the structural changes from binary AsSe to pseudo-binary (AsSe)(100-x)(AgI)(x) system and to study the influence of Ag and I incorporation on the local structure. (c) 2007 Published by Elsevier B.V.