X-ray diffraction is one of the most effective tools for the characterization of the stacking defects which occur frequently in clayminerals.Modelling of the diffraction patterns of oriented mounts is often used for obtaining structural information about the nature of stacking order. Manual matching of calculated and observed patterns is time consuming and the results are user dependent and esp...

In this programmatic paper we explain why a radical embodied cognitive neuroscience is needed. We argue for such a claim based on problems that have arisen in cognitive neuroscience for the project of localizing function to specific brain structures. The problems come from research concerned with functional and structural connectivity that strongly suggests that the function a brain region serv...

Extraction of reliable bond distances and angles for Ca10(VxP1-xO4)6F2 apatites using standard Rietveld refinement with Cu Kalpha X-ray powder data was significantly impaired by large imprecision for the O-atom coordinates. An initial attempt to apply crystal-chemical Rietveld refinements to the same compounds was partly successful, and exposed the problematic determination of two oxygen-metal-...

The Reverse Monte Carlo (RMC) method involves usually one or several thousands atoms, and modelling may start from random atomic positions. The Rietveld for disordered material (RDM) method needs a crystal structure as starting mean model, with hardly more than 20 independent atoms. The two methods are reconciled when a satisfying RDM model, enlarged by multiplying the cell axes, is subjected t...

The structure of triclinic disodium hafnium disilicate, Na2HfSi2O7, has been determined by laboratory powder X-ray diffraction and refined by the Rietveld refinement. The structure is a framework made of alternate layers of HfO6 octa-hedra and SiO4 tetra-hedra linked by common O atoms. Sodium atoms are located in the voids of the framework, aligned into tunnels along the [010] direction. Na2HfS...