Short range order diffuse intensity calculations in the cluster variation method

Reciprocal-space analysis of short-range-order intensities by the cluster-variation method.

A reciprocal space formulation of the Cluster Variation is used in order to extract effective pair interactions in alloys from experimental short-range order diffuse intensities. The method is applied to the analysis of the short range order contribution to the neutron diffuse scattering of a F e − 19.5%Al single crystal. A detailed comparison with real space methods is carried out for three di...

Spatial variation of short-range order in amorphous intergranular complexions

Short-range ordering and {1,1/2,0} diffuse intensity maxima in ZrNx

Diffuse intensity maxima in ZrNx caused by short-range ordering (SRO) of nitrogen atoms or vacancies are shown in electron diffraction patterns along four different low-index zone-axes. Analysis of the shape of the diffuse intensity was performed using an equation developed by Sauvage and Parthé [1]. Additional {1,1/2,0} diffuse intensity maxima were also observed and these have not been previo...

Short-range order in liquid aluminum chloride: ab initio molecular dynamics simulations and quantum-chemical calculations.

We use ab initio molecular dynamics simulations based on density-functional theory and quantum-chemistry calculations on molecular clusters to examine the structure of liquid AlCl3. In the past, conflicting descriptions of the short-range-order in molten AlCl3, based on either edge-sharing dimers or corner-sharing oligomers, have been proposed. This liquid also poses a simulation challenge, due...

Short-range order in ternary aUoy semiconductors

Atom arrangements in IH-V ternary aHoy semiconductors are discussed using a thermodynamic analysis in which the elastic strain caused by mixing is considered as the mixing enthalpy. In calculating the strain energy, both bond-stretching and bond-angl.e distortion are taken into account, and Martin's microscopic elastic constants are used. The results show that there is a preference for ordering...