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1.  The introduction of structure types into the Inorganic Crystal Structure Database ICSD 
The approach used and the progress made in the assignment of structure types to the crystal structures contained in the ICSD database are reported.
Both the approach used and the progress made in the assignment of structure types to the crystal structures contained in the ICSD database are reported. Extending earlier work, an hierarchical set of criteria for the separation of isopointal structures into isoconfigurational structure types is used. It is shown how these criteria, which include the space group (number), Wyckoff sequence and Pearson symbol, c/a ratio, β ranges, ANX formulae and, in certain cases, the necessary elements and forbidden elements, may be used to uniquely identify the representative structure types of the compounds contained in the ICSD database.
doi:10.1107/S0108767307038081
PMCID: PMC2525864  PMID: 17703075
Inorganic Crystal Structure Database; ICSD; structure types
2.  Diffraction with a coherent X-ray beam: dynamics and imaging. Erratum 
Erratum to Livet [Acta Cryst. (2007), A63, 63–87].
In the paper by Livet [Acta Cryst. (2007), A63, 63–87], equation (15) is incorrect. The correct equation is
doi:10.1107/S0108767307016248
PMCID: PMC2525863
coherent X-ray beams; dynamics of fluctuations; lensless imaging; small-angle set-ups
3.  Diffraction with a coherent X-ray beam: dynamics and imaging 
Techniques for coherent X-ray scattering measurements are detailed. Applications in the study of the dynamics of fluctuations and in lensless high-resolution imaging are described.
Methods for carrying out coherent X-ray scattering experiments are reviewed. The brilliance of the available synchrotron sources, the characteristics of the existing optics, the various ways of obtaining a beam of controlled coherence properties and the detectors used are summarized. Applications in the study of the dynamics of speckle patterns are described. In the case of soft condensed matter, the movement of inclusions like fillers in polymers or colloidal particles can be observed and these can reflect polymer or liquid-crystal fluctuations. In hard condensed-matter problems, like phase transitions, charge-density waves or phasons in quasicrystals, the study of speckle fluctuations provides new time-resolved methods. In the domain of lensless imaging, the coherent beam gives the modulus of the sample Fourier transform. If oversampling conditions are fulfilled, the phase can be obtained and the image in the direct space can be reconstructed. The forthcoming improvements of all these techniques are discussed.
doi:10.1107/S010876730605570X
PMCID: PMC2525861  PMID: 17301470
coherent X-ray beams; dynamics of fluctuations; lensless imaging; small-angle set-ups
4.  Coherent coexistence of nanodiamonds and carbon onions in icosahedral core-shell particles 
In icosahedral carbon nanoparticles, the diamond-like core can undergo a reversible topological transition into and coexist coherently with the onion shells.
The general approach for describing and designing complex hierarchical icosahedral structures is discussed. Structural models of icosahedral carbon nanoparticles in which the local arrangement of atoms is virtually identical to that in diamond are derived. It is shown that icosahedral diamond-like particles can be transformed into onion-like shell structures (and vice versa) by the consecutive smoothing (puckering) of atomic networks without disturbance of their topological integrity. The possibility of coherent coexistence of icosahedral diamond-like core with onion shells is shown.
doi:10.1107/S0108767307002723
PMCID: PMC2525862  PMID: 17301478
carbon onion; coherent coexistence; nanodiamond

Results 1-4 (4)