http://journals.iucr.org/j/issues/2008/04/00/isscontsbdy.html Journal of Applied Crystallography covers a wide range of crystallographic topics from the viewpoints of both techniques and theory. The journal presents papers on the application of crystallographic techniques and on the related apparatus and computer software. For many years, the Journal of Applied Crystallography has been the main vehicle for the publication of small-angle scattering papers and powder diffraction techniques. The journal is the primary place where crystallographic computer program information is published. Recent additions are a Cryocrystallography Papers section and a Software Reviews section. en Copyright (c) 2008 International Union of Crystallography 2008-08-01 International Union of Crystallography International Union of Crystallography http://journals.iucr.org urn:issn:0021-8898 Journal of Applied Crystallography covers a wide range of crystallographic topics from the viewpoints of both techniques and theory. The journal presents papers on the application of crystallographic techniques and on the related apparatus and computer software. For many years, the Journal of Applied Crystallography has been the main vehicle for the publication of small-angle scattering papers and powder diffraction techniques. The journal is the primary place where crystallographic computer program information is published. Recent additions are a Cryocrystallography Papers section and a Software Reviews section. text/html Journal of Applied Crystallography, Volume 41, Part 4, 2008 text yearly 6 2002-02-01T00:00+00:00 4 41 2008-08-01 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography 663 urn:issn:0021-8898 med@iucr.org August 2008 2008-08-01 http://journals.iucr.org/logos/rss10j.gif http://journals.iucr.org/j/issues/2008/04/00/isscontsbdy.html Still image http://scripts.iucr.org/cgi-bin/paper?ce5031 During the formation at low pH of resorcinol–formaldehyde gels with a structure in the micrometre range, small-angle X-ray scattering exhibits a non-monotonic intensity variation as a function of reaction time. The data are analyzed in terms of scattering by statistical fluctuations of polymer concentration, the amplitude of which is maximal close to the critical point for phase separation between polymer and solvent. The data do not carry any morphological information, but they unambiguously show that the driving force of the gel formation is a thermodynamic instability of the polymerizing solution. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Gommes, C.J. Job, N. Pirard, J.-P. Blacher, S. Goderis, B. 2008-06-06 doi:10.1107/S0021889808014994 International Union of Crystallography In situ small-angle X-ray scattering exhibits a non-monotonic evolution during the formation of resorcinol–formaldehyde gels. The data can be analyzed in terms of critical fluctuations, which points to a reaction-induced phase separation process. en small-angle X-ray scattering (SAXS) resorcinol–formaldehyde gels polymerization thermodynamic instability phase separation critical opalescence During the formation at low pH of resorcinol–formaldehyde gels with a structure in the micrometre range, small-angle X-ray scattering exhibits a non-monotonic intensity variation as a function of reaction time. The data are analyzed in terms of scattering by statistical fluctuations of polymer concentration, the amplitude of which is maximal close to the critical point for phase separation between polymer and solvent. The data do not carry any morphological information, but they unambiguously show that the driving force of the gel formation is a thermodynamic instability of the polymerizing solution. text/html Critical opalescence points to thermodynamic instability: relevance to small-angle X-ray scattering of resorcinol–formaldehyde gel formation at low pH text 4 41 2008-06-06 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 663 668 http://scripts.iucr.org/cgi-bin/paper?ce5041 How many of the theoretically densely distributed Bragg reflections of a quasicrystal can be observed employing an area detector and synchrotron radiation? How does the reflection density of a real quasicrystal change as a function of exposure time, and what is the minimum distance between reflections? What does the distribution of diffuse scattering look like? To answer these questions, the Bragg reflection density of a perfect icosahedral quasicrystal with composition Al64Cu23Fe13 was measured employing a novel type of single-photon-counting X-ray pixel detector, PILATUS 6M, which allows noise-free data collection with the extraordinarily large dynamic range of 20 bit. The reflection density was found to be two orders of magnitude lower than expected for a strictly quasiperiodic structure. Moreover, diffuse scattering reflects significant structural disorder, breaking six-dimensional F-lattice symmetry. These findings have some implications for the interpretation of physical properties. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Weber, T. Deloudi, S. Kobas, M. Yokoyama, Y. Inoue, A. Steurer, W. 2008-06-06 doi:10.1107/S0021889808014386 International Union of Crystallography The reciprocal space of the perfect icosahedral quasicrystal Al64Cu23Fe13 was explored employing synchrotron radiation and a novel type of single-photon-counting X-ray pixel detector, PILATUS 6M, which allows noise-free data collection with the extraordinarily large dynamic range of 20 bit. en quasicrystals X-ray diffraction PILATUS 6M How many of the theoretically densely distributed Bragg reflections of a quasicrystal can be observed employing an area detector and synchrotron radiation? How does the reflection density of a real quasicrystal change as a function of exposure time, and what is the minimum distance between reflections? What does the distribution of diffuse scattering look like? To answer these questions, the Bragg reflection density of a perfect icosahedral quasicrystal with composition Al64Cu23Fe13 was measured employing a novel type of single-photon-counting X-ray pixel detector, PILATUS 6M, which allows noise-free data collection with the extraordinarily large dynamic range of 20 bit. The reflection density was found to be two orders of magnitude lower than expected for a strictly quasiperiodic structure. Moreover, diffuse scattering reflects significant structural disorder, breaking six-dimensional F-lattice symmetry. These findings have some implications for the interpretation of physical properties. text/html Reciprocal-space imaging of a real quasicrystal. A feasibility study with PILATUS 6M text 4 41 2008-06-06 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 669 674 http://scripts.iucr.org/cgi-bin/paper?ks5183 Anomalous small-angle X-ray scattering (ASAXS) profiles of Zr80Pt20 ribbons have been measured at the Zr K absorption edge. By annealing the melt-spun ribbons at 800 K, well defined SAXS patterns from nanoquasicrystals were observed, although the compositions of the quasicrystals (QC) and the amorphous matrix have previously been reported to be the same. The SAXS intensities were found to show a small anomalous effect at the Zr K edge. Contrast analysis suggested that the origin of the small-angle scattering is a small compositional fluctuation coupled with a small density difference, which enhances SAXS intensity but reduces the anomalous effect. A constant ASAXS intensity ratio for QC microstructure suggests that the ratio of the composition difference to the density difference between QC and the amorphous matrix is almost constant for the ZrPt ribbons examined here. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Okuda, H. Fukumoto, T. Saida, J. Ochiai, S. Sasaki, S. Masunaga, H. 2008-06-14 doi:10.1107/S0021889808015781 International Union of Crystallography Anomalous small-angle scattering of quasicrystals in a Zr–Pt binary alloy was examined at the Zr K absorption edge. Small differences in both density and composition were found between the quasicrystals and the amorphous matrix. en Zr–Pt quasicrystal anomalous small-angle X-ray scattering Anomalous small-angle X-ray scattering (ASAXS) profiles of Zr80Pt20 ribbons have been measured at the Zr K absorption edge. By annealing the melt-spun ribbons at 800 K, well defined SAXS patterns from nanoquasicrystals were observed, although the compositions of the quasicrystals (QC) and the amorphous matrix have previously been reported to be the same. The SAXS intensities were found to show a small anomalous effect at the Zr K edge. Contrast analysis suggested that the origin of the small-angle scattering is a small compositional fluctuation coupled with a small density difference, which enhances SAXS intensity but reduces the anomalous effect. A constant ASAXS intensity ratio for QC microstructure suggests that the ratio of the composition difference to the density difference between QC and the amorphous matrix is almost constant for the ZrPt ribbons examined here. text/html Anomalous small-angle scattering from nanoquasicrystalline precipitates in Zr80Pt20 ribbons text 4 41 2008-06-14 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 675 679 http://scripts.iucr.org/cgi-bin/paper?ks5166 The crystal structure and the local atomic order of a series of nanocrystalline ZrO2–CaO solid solutions with varying CaO content were studied by synchrotron radiation X-ray powder diffraction and extended X-ray absorption fine structure (EXAFS) spectroscopy. These samples were synthesized by a pH-controlled nitrate–glycine gel-combustion process. For CaO contents up to 8 mol%, the t′ form of the tetragonal phase (c/a > 1) was identified, whereas for 10 and 12 mol% CaO, the t′′ form (c/a = 1; oxygen anions displaced from their ideal positions in the cubic phase) was detected. Finally, the cubic phase was observed for solid solutions with CaO content of 14 mol% CaO or higher. The t′/t′′ and t′′/cubic compositional boundaries were determined to be at 9 (1) and 13 (1) mol% CaO, respectively. The EXAFS study demonstrated that this transition is related to a tetragonal-to-cubic symmetry change of the first oxygen coordination shell around the Zr atoms. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Fábregas, I.O. Lamas, D.G. Walsöe de Reca, N.E. Fantini, M.C.A. Craievich, A.F. Prado, R.J. 2008-06-14 doi:10.1107/S0021889808013046 International Union of Crystallography The relationship between long- and short-range order in nanocrystalline ZrO2–CaO solid solutions was investigated by synchrotron radiation X-ray powder diffraction and extended X-ray absorption fine structure spectroscopy. en nanocrystalline powders zirconia–calcia X-ray powder diffraction extended X-ray absorption fine structure (EXAFS) The crystal structure and the local atomic order of a series of nanocrystalline ZrO2–CaO solid solutions with varying CaO content were studied by synchrotron radiation X-ray powder diffraction and extended X-ray absorption fine structure (EXAFS) spectroscopy. These samples were synthesized by a pH-controlled nitrate–glycine gel-combustion process. For CaO contents up to 8 mol%, the t′ form of the tetragonal phase (c/a > 1) was identified, whereas for 10 and 12 mol% CaO, the t′′ form (c/a = 1; oxygen anions displaced from their ideal positions in the cubic phase) was detected. Finally, the cubic phase was observed for solid solutions with CaO content of 14 mol% CaO or higher. The t′/t′′ and t′′/cubic compositional boundaries were determined to be at 9 (1) and 13 (1) mol% CaO, respectively. The EXAFS study demonstrated that this transition is related to a tetragonal-to-cubic symmetry change of the first oxygen coordination shell around the Zr atoms. text/html Synchrotron X-ray powder diffraction and extended X-ray absorption fine structure spectroscopy studies on nanocrystalline ZrO2–CaO solid solutions text 4 41 2008-06-14 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 680 689 http://scripts.iucr.org/cgi-bin/paper?he5406 Lithium-ion batteries are based on the principle of intercalation of lithium ions in host materials, both at the anode and at the cathode. These materials are in general crystalline and, during the operation of the battery, they undergo numerous phase transitions and structural rearrangements, often amplified by the presence of an applied potential difference. While in situ X-ray diffraction is an established technique in this field, in situ neutron diffraction is still in its pioneering stages and only a few attempts have been made to design an electrochemical cell suitable for these experiments. The technical development of such a device, along with a discussion of its serviceability to combine electrochemical measurements with neutron diffraction experiments, is hereby presented. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Rosciano, F. Holzapfel, M. Scheifele, W. Novák, P. 2008-07-01 doi:10.1107/S0021889808018025 International Union of Crystallography A new electrochemical cell for in situ neutron diffraction measurements on materials for lithium-ion batteries is presented. en Li-ion batteries in situ neutron diffraction electrode materials Lithium-ion batteries are based on the principle of intercalation of lithium ions in host materials, both at the anode and at the cathode. These materials are in general crystalline and, during the operation of the battery, they undergo numerous phase transitions and structural rearrangements, often amplified by the presence of an applied potential difference. While in situ X-ray diffraction is an established technique in this field, in situ neutron diffraction is still in its pioneering stages and only a few attempts have been made to design an electrochemical cell suitable for these experiments. The technical development of such a device, along with a discussion of its serviceability to combine electrochemical measurements with neutron diffraction experiments, is hereby presented. text/html A novel electrochemical cell for in situ neutron diffraction studies of electrode materials for lithium-ion batteries text 4 41 2008-07-01 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 690 694 http://scripts.iucr.org/cgi-bin/paper?fe5036 Recent X-ray optical experiments have validated previous theoretical work on focusing by bent crystals in Laue geometry. It was shown that a suitable choice of the crystal thickness significantly improves the focusing performance of the crystal by combining the dynamical focusing of the Borrmann triangle with the geometrical focusing obtained by the crystal bending. The best focus size achieved during the experiments was less than 5 µm and is in practice limited by the source demagnification for the considered setup. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Mocella, V. Ferrero, C. Hrdý, J. Wright, J. Pascarelli, S. Hoszowska, J. 2008-07-01 doi:10.1107/S0021889808017883 International Union of Crystallography An experimental verification is presented of the fact that focusing by bent crystals in Laue geometry is strongly improved by combining geometrical focusing with Borrmann triangle focusing effects, as suggested from the X-ray dynamical diffraction theory. en polychromatic focusing bent crystals Laue geometry X-ray dynamical diffraction theory Recent X-ray optical experiments have validated previous theoretical work on focusing by bent crystals in Laue geometry. It was shown that a suitable choice of the crystal thickness significantly improves the focusing performance of the crystal by combining the dynamical focusing of the Borrmann triangle with the geometrical focusing obtained by the crystal bending. The best focus size achieved during the experiments was less than 5 µm and is in practice limited by the source demagnification for the considered setup. text/html Experimental verification of dynamical diffraction focusing by a bent crystal wedge in Laue geometry text 4 41 2008-07-01 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 695 700 http://scripts.iucr.org/cgi-bin/paper?aj5105 A new procedure aimed at unfolding a two-dimensional powder diffraction image into both a one-dimensional azimuthal and a radial scan is presented. In this approach, the sample-to-detector distance is the only parameter that must be adjusted in a separate step by using a standard sample. The technique consists of three steps: tracking the beam centre as the local maximum of the self-convolution of the original two-dimensional map, detector tilt and rotation determination by an intensity-tensor diagonalization, and azimuthal/radial intensity integration by a conformal mapping of the original two-dimensional powder diffraction image. The X-ray powder diffraction (XRPD) intensity profile of the NIST Si 640c standard sample is used to test the performance. The results show the robustness of the method and its capability of efficiently tagging the pixels in a two-dimensional readout system by matching the ideal geometry of the detector to the real beam–sample–detector frame. The technique is a fast, versatile and user-friendly tool for the simultaneous analysis of both azimuthal and radial spectra of two-dimensional XRPD images. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Cervellino, A. Giannini, C. Guagliardi, A. Ladisa, M. 2008-07-01 doi:10.1107/S0021889808019092 International Union of Crystallography A new procedure aimed at unfolding a two-dimensional powder diffraction image into both a one-dimensional azimuthal and a radial scan is presented. en X-ray powder diffraction conformal mapping A new procedure aimed at unfolding a two-dimensional powder diffraction image into both a one-dimensional azimuthal and a radial scan is presented. In this approach, the sample-to-detector distance is the only parameter that must be adjusted in a separate step by using a standard sample. The technique consists of three steps: tracking the beam centre as the local maximum of the self-convolution of the original two-dimensional map, detector tilt and rotation determination by an intensity-tensor diagonalization, and azimuthal/radial intensity integration by a conformal mapping of the original two-dimensional powder diffraction image. The X-ray powder diffraction (XRPD) intensity profile of the NIST Si 640c standard sample is used to test the performance. The results show the robustness of the method and its capability of efficiently tagging the pixels in a two-dimensional readout system by matching the ideal geometry of the detector to the real beam–sample–detector frame. The technique is a fast, versatile and user-friendly tool for the simultaneous analysis of both azimuthal and radial spectra of two-dimensional XRPD images. text/html Unfolding a two-dimensional powder diffraction image: conformal mapping text 4 41 2008-07-01 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 701 704 http://scripts.iucr.org/cgi-bin/paper?ko5058 Reverse Monte Carlo (RMC) refinements using a combined real-space fit of the neutron/X-ray total scattering pair-distribution function (PDF) and the extended X-ray absorption fine structure (EXAFS) were developed and implemented as an extension to the public domain computer software RMCProfile. The effectiveness of combined PDF/EXAFS RMC refinements was tested using perovskite Ca(Zr,Ti)O3 solid solutions. The analyses revealed that combining two types of data yields correct distributions of the Ti—O and Zr—O distances that could not be recovered using either of the techniques alone because of the substantial overlap between the Ti—O and Zr—O partial PDFs. The combined refinements enabled reasonably accurate reproduction of most of the local structure characteristics, including the dependence of Ca displacements on the local B-cation coordination around Ca. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Krayzman, V. Levin, I. Tucker, M.G. 2008-06-06 doi:10.1107/S0021889808013277 International Union of Crystallography Reverse Monte Carlo refinements using a combined real-space fit of the neutron/X-ray total scattering pair-distribution function and the extended X-ray absorption fine structure were developed and implemented as an extension to the public domain computer software RMCProfile. The effectiveness of the method was tested using perovskite Ca(Zr,Ti)O3 solid solutions. en reverse Monte Carlo refinement neutron/X-ray total scattering pair-distribution functions extended X-ray absorption fine structure (EXAFS) computer programs RMCProfile Reverse Monte Carlo (RMC) refinements using a combined real-space fit of the neutron/X-ray total scattering pair-distribution function (PDF) and the extended X-ray absorption fine structure (EXAFS) were developed and implemented as an extension to the public domain computer software RMCProfile. The effectiveness of combined PDF/EXAFS RMC refinements was tested using perovskite Ca(Zr,Ti)O3 solid solutions. The analyses revealed that combining two types of data yields correct distributions of the Ti—O and Zr—O distances that could not be recovered using either of the techniques alone because of the substantial overlap between the Ti—O and Zr—O partial PDFs. The combined refinements enabled reasonably accurate reproduction of most of the local structure characteristics, including the dependence of Ca displacements on the local B-cation coordination around Ca. text/html Simultaneous reverse Monte Carlo refinements of local structures in perovskite solid solutions using EXAFS and the total scattering pair-distribution function text 4 41 2008-06-06 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 705 714 http://scripts.iucr.org/cgi-bin/paper?ce5033 A method for collimation correction and combination of anisotropic scattering patterns recorded in tandem experiments is proposed. It includes both an advanced two-dimensional extrapolation procedure for the center of the pattern and (compared with the `blind deconvolution' method) a more justified procedure for desmearing from an unknown broad primary beam profile. This semi-blind deconvolution rests on the availability of unsmeared data in a region of the smeared image. Materials exhibiting both ultra-small-angle X-ray scattering (USAXS) and small-angle X-ray scattering (SAXS) must be studied in both angular bands (tandem experiment), in order to collect the complete range of discrete scattering for nanostructure analysis. Merging of the patterns requires desmearing of at least the SAXS pattern from its point-spread function, i.e. the primary beam profile. The distorting effect of single-band experiments on the reconstructed nanostructure of polymer materials is demonstrated. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Stribeck, N. Nöchel, U. 2008-06-06 doi:10.1107/S0021889808015021 International Union of Crystallography The combination of two-dimensional scattering patterns measured with different instruments requires collimation correction. The method is demonstrated by small- and ultra-small-angle X-ray scattering of polymer fiber materials. en ultra-small-angle X-ray scattering (USAXS) small-angle X-ray scattering (SAXS) collimation correction polymers nanostructures A method for collimation correction and combination of anisotropic scattering patterns recorded in tandem experiments is proposed. It includes both an advanced two-dimensional extrapolation procedure for the center of the pattern and (compared with the `blind deconvolution' method) a more justified procedure for desmearing from an unknown broad primary beam profile. This semi-blind deconvolution rests on the availability of unsmeared data in a region of the smeared image. Materials exhibiting both ultra-small-angle X-ray scattering (USAXS) and small-angle X-ray scattering (SAXS) must be studied in both angular bands (tandem experiment), in order to collect the complete range of discrete scattering for nanostructure analysis. Merging of the patterns requires desmearing of at least the SAXS pattern from its point-spread function, i.e. the primary beam profile. The distorting effect of single-band experiments on the reconstructed nanostructure of polymer materials is demonstrated. text/html A method for merging of ultra-small-angle X-ray scattering and smeared small-angle X-ray scattering patterns of fibers text 4 41 2008-06-06 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 715 722 http://scripts.iucr.org/cgi-bin/paper?aj5102 A small-angle light scattering (SALS) instrument with a high resolution at low angles and a high signal-to-noise ratio has been developed. Both a wide dynamic range and a wide scattering vector range are achieved using a two-dimensional array of complementary metal oxide semiconductor image sensors. These instrument characteristics have enabled us to obtain high-quality light scattering data from soft matter systems. This setup is especially well suited to studies of systems with a weak scattering power and/or a time-dependent structure evolution in a wide spatial range from submicrometre to submillimetre. An application of this instrument to a polyelectrolyte blend and an extremely thin blend film are reported. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Nishida, K. Ogawa, H. Matsuba, G. Konishi, T. Kanaya, T. 2008-06-06 doi:10.1107/S002188980801265X International Union of Crystallography A small-angle light scattering instrument with a high resolution at low angles and a high signal-to-noise ratio has been developed. The characteristics of this instrument make it suitable for soft matter studies. en small-angle light scattering (SALS) complementary metal oxide semiconductor (CMOS) image sensors soft matter instrument design A small-angle light scattering (SALS) instrument with a high resolution at low angles and a high signal-to-noise ratio has been developed. Both a wide dynamic range and a wide scattering vector range are achieved using a two-dimensional array of complementary metal oxide semiconductor image sensors. These instrument characteristics have enabled us to obtain high-quality light scattering data from soft matter systems. This setup is especially well suited to studies of systems with a weak scattering power and/or a time-dependent structure evolution in a wide spatial range from submicrometre to submillimetre. An application of this instrument to a polyelectrolyte blend and an extremely thin blend film are reported. text/html A high-resolution small-angle light scattering instrument for soft matter studies text 4 41 2008-06-06 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 723 728 http://scripts.iucr.org/cgi-bin/paper?dd5039 The results are presented of a feasibility study for the application of absorption corrections to macromolecular crystallographic X-ray diffraction data using a three-dimensional crystal model generated photographically. The model allows path lengths through the crystal, the solvent and the crystal mount system to be determined. The approach has been tested on the macromolecular crystallography beamline ID23-1 at the ESRF in Grenoble using a model insulin system with the standard mini diffractometer facilities, which incorporate high-quality camera systems for sample alignment. Data from the insulin crystal at low incident beam energy (6.0 keV or 2.1 Å) were recorded and processed using this approach. The resulting data are compared against those treated using an empirical method and show significant improvement. The methods described here are of general interest, particularly for long-wavelength X-ray work, and may also be applied to account for absorption effects in neutron crystallography. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Leal, R.M.F. Teixeira, S.C.M. Rey, V. Forsyth, V.T. Mitchell, E.P. 2008-06-06 doi:10.1107/S0021889808011898 International Union of Crystallography A new method has been developed for the application of absorption corrections to macromolecular crystallographic X-ray diffraction data. The approach uses a three-dimensional crystal model generated photographically so that path lengths through the crystal, the solvent and the crystal mount system can be determined reliably. Data from an insulin crystal at low incident beam energy have been recorded and processed using this approach. en absorption correction macromolecular crystallography long-wavelength X-ray diffraction neutron crystallography The results are presented of a feasibility study for the application of absorption corrections to macromolecular crystallographic X-ray diffraction data using a three-dimensional crystal model generated photographically. The model allows path lengths through the crystal, the solvent and the crystal mount system to be determined. The approach has been tested on the macromolecular crystallography beamline ID23-1 at the ESRF in Grenoble using a model insulin system with the standard mini diffractometer facilities, which incorporate high-quality camera systems for sample alignment. Data from the insulin crystal at low incident beam energy (6.0 keV or 2.1 Å) were recorded and processed using this approach. The resulting data are compared against those treated using an empirical method and show significant improvement. The methods described here are of general interest, particularly for long-wavelength X-ray work, and may also be applied to account for absorption effects in neutron crystallography. text/html Absorption correction based on a three-dimensional model reconstruction from visual images text 4 41 2008-06-06 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 729 737 http://scripts.iucr.org/cgi-bin/paper?ks5170 A YNi2B2C single crystal containing traces of foreign phases was inspected by means of neutron and X-ray diffraction as well as scanning electron microscopy and X-ray spectroscopy methods. The diffraction patterns obtained from the experiments look similar to those expected for a superstructure. Nevertheless, they can be interpreted as crystallographically oriented precipitations of YB2C2 and Ni2B within the YNi2B2C crystal, formed during the cooling process. The orientation relation between the lattices was obtained from experimental neutron and X-ray data. Structure refinements of the collected X-ray data were performed by separation of the intensity data of the individual phases. Scanning electron microscopy images of the inclusions found on a polished cross section of the crystal are presented; their chemical composition was determined using wavelength-dispersive X-ray analysis. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Weissbach, T. Leisegang, T. Kreyssig, A. Frontzek, M. Hoffmann, J.-U. Souptel, D. Köhler, A. Behr, G. Paufler, P. Meyer, D.C. 2008-06-14 doi:10.1107/S002188980801279X International Union of Crystallography Diffraction patterns obtained by X-ray and neutron diffraction are presented for several crystalline phases of the Y–Ni–B–C system. en single-crystal diffraction methods intermetallic compounds A YNi2B2C single crystal containing traces of foreign phases was inspected by means of neutron and X-ray diffraction as well as scanning electron microscopy and X-ray spectroscopy methods. The diffraction patterns obtained from the experiments look similar to those expected for a superstructure. Nevertheless, they can be interpreted as crystallographically oriented precipitations of YB2C2 and Ni2B within the YNi2B2C crystal, formed during the cooling process. The orientation relation between the lattices was obtained from experimental neutron and X-ray data. Structure refinements of the collected X-ray data were performed by separation of the intensity data of the individual phases. Scanning electron microscopy images of the inclusions found on a polished cross section of the crystal are presented; their chemical composition was determined using wavelength-dispersive X-ray analysis. text/html Intergrowth of several solid phases from the Y–Ni–B–C system in a large YNi2B2C crystal text 4 41 2008-06-14 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 738 746 http://scripts.iucr.org/cgi-bin/paper?ks5176 X-ray and electron backscatter diffraction (EBSD) have been applied to investigate misorientation distributions in copper single crystals plastically deformed in single and multiple slip. The misorientation distributions are represented by `rocking curves' about specific rotation axes. Very good agreement for the rocking curves established by the two methods was obtained, despite the large difference between their resolution depths. Following this agreement, a new rotation axis imaging scheme, based on the EBSD data, is proposed in order to visualize the crystallite blocks and characterize the nature of their dislocation boundaries. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Borbély, A. Maurice, C. Driver, J.H. 2008-06-21 doi:10.1107/S0021889808015768 International Union of Crystallography The misorientation distributions about given rotation axes in deformed Cu single crystals are shown to be the same for X-ray diffraction (as standard rocking curves) and for high-resolution electron backscattered diffraction (as virtual rocking curves calculated from the orientation data). A new rotation axis imaging scheme is proposed for electron backscattered diffraction maps to highlight specific features of the deformation-induced sub-boundaries. en crystal deformation misorientation distributions X ray diffraction electron backscatter diffraction X-ray and electron backscatter diffraction (EBSD) have been applied to investigate misorientation distributions in copper single crystals plastically deformed in single and multiple slip. The misorientation distributions are represented by `rocking curves' about specific rotation axes. Very good agreement for the rocking curves established by the two methods was obtained, despite the large difference between their resolution depths. Following this agreement, a new rotation axis imaging scheme, based on the EBSD data, is proposed in order to visualize the crystallite blocks and characterize the nature of their dislocation boundaries. text/html Rotation axis analysis of deformed crystals by X-rays and electrons text 4 41 2008-06-21 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 747 753 http://scripts.iucr.org/cgi-bin/paper?ks5175 A focusing Laue diffractometer for high-energy X-rays of up to 300 keV in a laboratory environment is presented. The long attenuation length for X-ray energies above 50 keV allows for the non-destructive investigation of structural issues and bulk properties of single crystals. Furthermore, massive sample environments such as high-temperature furnaces can be used more easily. With an area detector, anisotropic mosaicities or crystallite structure become visible without any rocking movement of the sample. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Stockmeier, M. Magerl, A. 2008-06-21 doi:10.1107/S0021889808012417 International Union of Crystallography A focusing Laue diffractometer is presented for high-energy X-rays of up to 300 keV in a laboratory environment. The long attenuation length for high-energy X-rays allows for the non-destructive investigation of structural issues and bulk properties of single crystals. en focusing Laue diffractometer high-energy X-rays non-destructive investigation bulk crystals A focusing Laue diffractometer for high-energy X-rays of up to 300 keV in a laboratory environment is presented. The long attenuation length for X-ray energies above 50 keV allows for the non-destructive investigation of structural issues and bulk properties of single crystals. Furthermore, massive sample environments such as high-temperature furnaces can be used more easily. With an area detector, anisotropic mosaicities or crystallite structure become visible without any rocking movement of the sample. text/html A focusing Laue diffractometer for the investigation of bulk crystals text 4 41 2008-06-21 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 754 760 http://scripts.iucr.org/cgi-bin/paper?he5403 Atomic structures of proteins determined via protein crystallography contain numerous solvent atoms. The experimental data for the determination of a water molecule's O-atom position is often a small contained blob of unidentified electron density. Unfortunately, the nature of crystallographic refinement lets poorly placed solvent atoms bias the future refined positions of all atoms in the crystal structure. This research article presents the technique of omit-maps applied to remove the bias introduced by poorly determined solvent atoms, enabling the identification of incorrectly placed water molecules in partially refined crystal structures. A total of 160 protein crystal structures with 45 912 distinct water molecules were processed using this technique. Most of the water molecules in the deposited structures were well justified. However, a few of the solvent atoms in this test data set changed appreciably in position, displacement parameter or electron density when fitted to the solvent omit-map, raising questions about how much experimental support exists for these solvent atoms. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Brown, E.N. 2008-06-21 doi:10.1107/S0021889808016609 International Union of Crystallography A method is presented for creating an omit-map on the solvent of an X-ray crystal structure; this map can be used to refine and remove poorly resolved water molecules. en X-ray diffraction protein crystallography omit-maps solvent water molecules computer programs Atomic structures of proteins determined via protein crystallography contain numerous solvent atoms. The experimental data for the determination of a water molecule's O-atom position is often a small contained blob of unidentified electron density. Unfortunately, the nature of crystallographic refinement lets poorly placed solvent atoms bias the future refined positions of all atoms in the crystal structure. This research article presents the technique of omit-maps applied to remove the bias introduced by poorly determined solvent atoms, enabling the identification of incorrectly placed water molecules in partially refined crystal structures. A total of 160 protein crystal structures with 45 912 distinct water molecules were processed using this technique. Most of the water molecules in the deposited structures were well justified. However, a few of the solvent atoms in this test data set changed appreciably in position, displacement parameter or electron density when fitted to the solvent omit-map, raising questions about how much experimental support exists for these solvent atoms. text/html Removing bias from solvent atoms in electron density maps text 4 41 2008-06-21 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 761 767 http://scripts.iucr.org/cgi-bin/paper?hx5067 It is demonstrated that many X-ray measurements, especially at grazing incidence, allow continuous data acquisition during stepped scans without deadtime for diffractometer motor motions. Analyzing the deviation from the ideal trajectory during independent motor movements, it is found that the deviation from the direct line connecting two data points in reciprocal space is very small for large volumes of reciprocal space. A synchronization algorithm to determine coordinated motor movements that follow the direct line connecting the data points is presented. Verification experiments on a six-circle diffractometer demonstrate the validity of the approach. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Shayduk, R. Braun, W. 2008-07-16 doi:10.1107/S0021889808018256 International Union of Crystallography The positioning errors in an X-ray measurement with data acquisition during motor movements have been analyzed. The results show that during most scans in standard geometries data can be acquired even during uncoordinated motor movements between the measurement points without loss of accuracy. en X-ray diffraction continuous data acquisition stepped scans It is demonstrated that many X-ray measurements, especially at grazing incidence, allow continuous data acquisition during stepped scans without deadtime for diffractometer motor motions. Analyzing the deviation from the ideal trajectory during independent motor movements, it is found that the deviation from the direct line connecting two data points in reciprocal space is very small for large volumes of reciprocal space. A synchronization algorithm to determine coordinated motor movements that follow the direct line connecting the data points is presented. Verification experiments on a six-circle diffractometer demonstrate the validity of the approach. text/html Positioning errors during stepped scans in X-ray crystallography text 4 41 2008-07-16 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 768 775 http://scripts.iucr.org/cgi-bin/paper?ko5064 The temperature-dependent post-perovskite structure model of MgSiO3 is reinvestigated through analysis of the atom-pair distances observed experimentally via Fourier transformation of X-ray diffraction and diffuse scattering, the total X-ray scattering, from CaIrO3. In contrast to the results of a previous Rietveld structure refinement, which shows a negative or null thermal expansion of Ir—O and Ca—O bond lengths within the average long-range structure, visual inspection of these atom-pair distances in the pair-distribution function, in addition to structure models fitted through least-squares refinement to this local-structure data, strongly suggests that these distances between atom pairs increase with temperature. The average long-range structure of CaIrO3, visible from Rietveld structure refinement, is distinct from the short-range structure (≤ 18 Å) at all of the temperatures examined in this study (325–1114 K) and is reproduced in structure models fitted to the pair-distribution function extending to sufficiently long atom-pair distances (≥ 50 Å). While previous data obtained with Rietveld structure refinement show the iridium coordination octahedra to distort with increasing temperature, models of the short-range structure demonstrate that these polyhedra instead reduce distortion and rotate in a manner similar to that occurring in the perovskite structure. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Martin, C.D. 2008-07-16 doi:10.1107/S0021889808019365 International Union of Crystallography The temperature-dependent post-perovskite structure model of MgSiO3 is reinvestigated through analysis of the total X-ray scattering from CaIrO3. In contrast to the results of a previous Rietveld structure refinement, showing a negative thermal expansion of Ir—O and Ca—O bond lengths, atom-pair distances in the pair-distribution function prove that these distances between atom pairs increase with temperature. en pair-distribution function temperature dependence modeling post-perovskites MgSiO3 CaIrO3 lower mantle The temperature-dependent post-perovskite structure model of MgSiO3 is reinvestigated through analysis of the atom-pair distances observed experimentally via Fourier transformation of X-ray diffraction and diffuse scattering, the total X-ray scattering, from CaIrO3. In contrast to the results of a previous Rietveld structure refinement, which shows a negative or null thermal expansion of Ir—O and Ca—O bond lengths within the average long-range structure, visual inspection of these atom-pair distances in the pair-distribution function, in addition to structure models fitted through least-squares refinement to this local-structure data, strongly suggests that these distances between atom pairs increase with temperature. The average long-range structure of CaIrO3, visible from Rietveld structure refinement, is distinct from the short-range structure (≤ 18 Å) at all of the temperatures examined in this study (325–1114 K) and is reproduced in structure models fitted to the pair-distribution function extending to sufficiently long atom-pair distances (≥ 50 Å). While previous data obtained with Rietveld structure refinement show the iridium coordination octahedra to distort with increasing temperature, models of the short-range structure demonstrate that these polyhedra instead reduce distortion and rotate in a manner similar to that occurring in the perovskite structure. text/html The local post-perovskite structure and its temperature dependence: atom-pair distances in CaIrO3 revealed through analysis of the total X-ray scattering at high temperatures text 4 41 2008-07-16 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 776 783 http://scripts.iucr.org/cgi-bin/paper?kk5026 A new procedure for performing structural analysis of crystalline materials from diffraction data, using internal coordinates, is described. For starting information only unit-cell content, space group, chemical formula, molecular connectivity and a limited amount of diffraction data are required. After first selecting a number of solutions using a Monte Carlo approach with severe filters, which reject the most unrealistic solutions, genetic algorithms (crossover and mutations) are applied. In fact, the initial selection step alone is, frequently, a powerful tool for discovering structures, without recourse to the genetic algorithms. The procedure, while suffering from the limitation that connectivity must be known, is effective in cases where direct methods are not applicable because the diffraction data are scarce, are limited to low diffraction angles or are missing in specific portions of the reciprocal space. The main features of the algorithm are described and examples of validation given. The routines are now available as part of the freely distributed general-purpose program TRY. The program is available on the Web at http://www.theochem.unisa.it/try.html. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Immirzi, A. Erra, L. Tedesco, C. 2008-07-16 doi:10.1107/S0021889808020074 International Union of Crystallography A new procedure for performing structural analysis of crystalline materials from diffraction data by random search and genetic algorithms is described. en structural analysis sparse diffraction data random search algorithms genetic algorithms computer programs TRY A new procedure for performing structural analysis of crystalline materials from diffraction data, using internal coordinates, is described. For starting information only unit-cell content, space group, chemical formula, molecular connectivity and a limited amount of diffraction data are required. After first selecting a number of solutions using a Monte Carlo approach with severe filters, which reject the most unrealistic solutions, genetic algorithms (crossover and mutations) are applied. In fact, the initial selection step alone is, frequently, a powerful tool for discovering structures, without recourse to the genetic algorithms. The procedure, while suffering from the limitation that connectivity must be known, is effective in cases where direct methods are not applicable because the diffraction data are scarce, are limited to low diffraction angles or are missing in specific portions of the reciprocal space. The main features of the algorithm are described and examples of validation given. The routines are now available as part of the freely distributed general-purpose program TRY. The program is available on the Web at http://www.theochem.unisa.it/try.html. text/html Finding crystal structures from few diffraction data by a combination of a random search with genetic algorithms text 4 41 2008-07-16 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography research papers 784 790 http://scripts.iucr.org/cgi-bin/paper?do5042 Capillary tubes have many advantages over multi-well plates for macromolecular crystal growth and handling, including the possibility of in situ structure determination. To obtain complete high-resolution X-ray data sets, cryopreservation protocols must be developed to prevent crystalline ice formation and preserve macromolecular crystal order. The minimum glycerol concentrations required to vitrify aqueous solutions during plunging into liquid nitrogen and liquid propane have been determined for capillary diameters from 3.3 mm to 150 µm. For the smallest diameter, the required glycerol concentrations are 30%(w/v) in nitrogen and 20%(w/v) in propane, corresponding to cooling rates of ∼800 and ∼7000 K s−1, respectively. These concentrations are much larger than are required in current best practice using crystals in loops or on microfabricated mounts. In additon, the relation between the minimum cooling rate for vitrification and glycerol concentration has been estimated; this relation is of fundamental importance in developing rational cryopreservation protocols. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Warkentin, M. Stanislavskaia, V. Hammes, K. Thorne, R.E. 2008-07-01 doi:10.1107/S0021889808018451 International Union of Crystallography The minimum glycerol concentrations required to obtain vitreous ice during plunge cooling of capillaries in liquid propane and nitrogen are determined as a function of capillary diameter and cooling rate. Capillary-based cryocrystallography will require much larger cryoprotectant concentrations than can be achieved with loop or microfabricated X-ray mount-based methods. en cryocrystallography capillaries protein crystallography high throughput cryopreservation glycerol vitrification Capillary tubes have many advantages over multi-well plates for macromolecular crystal growth and handling, including the possibility of in situ structure determination. To obtain complete high-resolution X-ray data sets, cryopreservation protocols must be developed to prevent crystalline ice formation and preserve macromolecular crystal order. The minimum glycerol concentrations required to vitrify aqueous solutions during plunging into liquid nitrogen and liquid propane have been determined for capillary diameters from 3.3 mm to 150 µm. For the smallest diameter, the required glycerol concentrations are 30%(w/v) in nitrogen and 20%(w/v) in propane, corresponding to cooling rates of ∼800 and ∼7000 K s−1, respectively. These concentrations are much larger than are required in current best practice using crystals in loops or on microfabricated mounts. In additon, the relation between the minimum cooling rate for vitrification and glycerol concentration has been estimated; this relation is of fundamental importance in developing rational cryopreservation protocols. text/html Cryocrystallography in capillaries: critical glycerol concentrations and cooling rates text 4 41 2008-07-01 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography cryocrystallography papers 791 797 http://scripts.iucr.org/cgi-bin/paper?ks5182 Pre-polished Ge(111) single-crystal wafers were deformed just below the melting temperature to prepare point-focusing Johansson monochromator crystals. The (111) lattice plane had curvature 2R in the focusing plane and R perpendicular to it, with a hemispherical inner surface with a radius of R = 600 mm. By using Cu Kα radiation, the diverging X-ray beam was focused onto a small spot. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Okuda, H. Nakajima, K. Fujiwara, K. Morishita, K. Ochiai, S. 2008-06-14 doi:10.1107/S0021889808016282 International Union of Crystallography A point-focusing Johansson monochromator crystal prepared by hot-pressing a Ge single-crystal wafer is demonstrated. By using 333 diffraction, Cu Kα radiation was focused onto a small spot. en Johansson monochromator Ge hot plastic deformation Pre-polished Ge(111) single-crystal wafers were deformed just below the melting temperature to prepare point-focusing Johansson monochromator crystals. The (111) lattice plane had curvature 2R in the focusing plane and R perpendicular to it, with a hemispherical inner surface with a radius of R = 600 mm. By using Cu Kα radiation, the diverging X-ray beam was focused onto a small spot. text/html Point-focusing monochromator crystal realized by hot plastic deformation of a Ge wafer text 4 41 2008-06-14 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography short communications 798 799 http://scripts.iucr.org/cgi-bin/paper?cg5077 In this paper, the electron backscatter diffraction (EBSD) technique is used to determine the orientations of α-cristobalite dendrites. The two branches of the cross-shaped α-cristobalite dendrite extend along the crystallographic directions [100] and [010], but no branches develop along 〈001〉. A new kind of twinning relationship is found between two α-cristobalite dendrites. The twin axes are [110], [111] and [\bar 1\bar 11], and the twin planes are (111) and (\bar 1\bar 11). It is shown that crystallographic symmetry controls the dendrite morphology and dendrite aggregation. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Zhao, S. Yang, M. Xu, H. Zhang, S. 2008-06-14 doi:10.1107/S002188980801635X International Union of Crystallography Electron backscatter diffraction and pole figures have been used to determine that the branches in α-cristobalite dendrite extend along [100] and [010] but not along 〈001〉. A new kind of twinning is found between two α-cristobalite dendrites: the twin axes are [110], [111] and [\bar1 \bar11], and the twin planes are (111) and (\bar 1 \bar 11). en α-cristobalite dendrites electron backscatter diffraction branching twinning In this paper, the electron backscatter diffraction (EBSD) technique is used to determine the orientations of α-cristobalite dendrites. The two branches of the cross-shaped α-cristobalite dendrite extend along the crystallographic directions [100] and [010], but no branches develop along 〈001〉. A new kind of twinning relationship is found between two α-cristobalite dendrites. The twin axes are [110], [111] and [\bar 1\bar 11], and the twin planes are (111) and (\bar 1\bar 11). It is shown that crystallographic symmetry controls the dendrite morphology and dendrite aggregation. text/html Branching and twinning in α-cristobalite dendrites: an electron backscatter diffraction study text 4 41 2008-06-14 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography short communications 800 802 http://scripts.iucr.org/cgi-bin/paper?cg5082 The symmetry-reduced misorientation, i.e. disorientation, between two crystals is represented in the angle–axis format, and the maximum disorientation angle between any two lattices of the 32 point groups is obtained by constructing the fundamental zone of the associated misorientation space (i.e. Rodrigues–Frank space) using quaternion algebra. A computer program based on vertex enumeration was designed to automatically calculate the vertices of these fundamental zones and to seek the maximum disorientation angles and respective rotation axes. Of the C_{32}^2 = 528 possible combinations of any two crystals, 129 pairs give rise to incompletely bounded fundamental zones (i.e. zones having at least one unbounded direction in R3); these correspond to a maximum disorientation angle of 180° (the trivial value). The other 399 pairs produce fully bounded fundamental zones that lead to nine different nontrivial maximum disorientation angles; these are 56.60, 61.86, 62.80, 90, 90.98, 93.84, 98.42, 104.48 and 120°. The associated rotation axes were obtained and are plotted in stereographic projection. These angles and axes are solely determined by the symmetries of the point groups under consideration, and the only input data needed are the symmetry operators of the lattices. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 He, Y. Jonas, J.J. 2008-06-21 doi:10.1107/S0021889808016373 International Union of Crystallography The maximum disorientation angles between crystals of the 32 point groups were evaluated (together with their corresponding rotation axes) by constructing the fundamental zones of Rodrigues–Frank space. Only ten different maximum angles are possible for the 528 pairs of lattices. en disorientation misorientation point groups Rodrigues–Frank space quaternions The symmetry-reduced misorientation, i.e. disorientation, between two crystals is represented in the angle–axis format, and the maximum disorientation angle between any two lattices of the 32 point groups is obtained by constructing the fundamental zone of the associated misorientation space (i.e. Rodrigues–Frank space) using quaternion algebra. A computer program based on vertex enumeration was designed to automatically calculate the vertices of these fundamental zones and to seek the maximum disorientation angles and respective rotation axes. Of the C_{32}^2 = 528 possible combinations of any two crystals, 129 pairs give rise to incompletely bounded fundamental zones (i.e. zones having at least one unbounded direction in R3); these correspond to a maximum disorientation angle of 180° (the trivial value). The other 399 pairs produce fully bounded fundamental zones that lead to nine different nontrivial maximum disorientation angles; these are 56.60, 61.86, 62.80, 90, 90.98, 93.84, 98.42, 104.48 and 120°. The associated rotation axes were obtained and are plotted in stereographic projection. These angles and axes are solely determined by the symmetries of the point groups under consideration, and the only input data needed are the symmetry operators of the lattices. text/html Maximum disorientation angles between crystals of any point groups and their corresponding rotation axes text 4 41 2008-06-21 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography short communications 803 807 http://scripts.iucr.org/cgi-bin/paper?he5407 Recent revisions to the CIF standard, the growing number of dictionaries and the critical role played by CIF in the IUCr publication process led the IUCr to fund a two-year project to upgrade portions of the existing CIF software base to support longer lines and more rigorous validation of CIFs against multiple layered dictionaries. A database-based approach to validation to ensure compliance with data-range and enumeration specifications, to ensure compliance with parent–child relationships, and to detect missing and duplicated tags is presented here. This approach to validation is being extended to support the handling of binary synchrotron imgCIF data. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Todorov, G. Bernstein, H.J. 2008-06-06 doi:10.1107/S002188980801385X International Union of Crystallography A database-based approach to validation of CIFs to ensure compliance with data-range and enumeration specifications, to ensure compliance with parent–child relationships, and to detect missing and duplicated tags is presented. en CIF validation binary imgCIF data compliance Recent revisions to the CIF standard, the growing number of dictionaries and the critical role played by CIF in the IUCr publication process led the IUCr to fund a two-year project to upgrade portions of the existing CIF software base to support longer lines and more rigorous validation of CIFs against multiple layered dictionaries. A database-based approach to validation to ensure compliance with data-range and enumeration specifications, to ensure compliance with parent–child relationships, and to detect missing and duplicated tags is presented here. This approach to validation is being extended to support the handling of binary synchrotron imgCIF data. text/html VCIF2: extended CIF validation software text 4 41 2008-06-06 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography CIF applications 808 810 http://scripts.iucr.org/cgi-bin/paper?ce5042 An editing toolkit has been developed to allow authors to create enhanced interactive figures for publication in crystallography journals. The visualization engine is Jmol, a Java program that can be manipulated as an applet in a web browser. The toolkit provides user-friendly widgets to manipulate the graphics state of Jmol, and persistent storage of graphics state, scripts and associated data files. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 McMahon, B. Hanson, R.M. 2008-07-01 doi:10.1107/S0021889808015616 International Union of Crystallography A description is provided of a software utility for creating interactive figures derived from crystal structures using the Java program Jmol. en computer programs interactive graphics molecular visualization An editing toolkit has been developed to allow authors to create enhanced interactive figures for publication in crystallography journals. The visualization engine is Jmol, a Java program that can be manipulated as an applet in a web browser. The toolkit provides user-friendly widgets to manipulate the graphics state of Jmol, and persistent storage of graphics state, scripts and associated data files. text/html A toolkit for publishing enhanced figures text 4 41 2008-07-01 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography computer programs 811 814 http://scripts.iucr.org/cgi-bin/paper?hx5069 QUALX is a new computer program for phase identification using powder diffraction data. It uses the Powder Diffraction File database, where a search for the phase best matching the experimental powder diffraction pattern is carried out. The program is characterized by a high level of automation: the traditional steps aimed at interpreting the experimental pattern before the search (background estimation, peak search, peak intensity evaluation) are executed automatically. The search may be carried out via constraints on compound name and/or chemical elements. In addition, several graphical options requested interactively enable the user to perform zero point correction evaluation, Kα2 stripping and smoothing. The program, written in Fortran95 and C++, runs on PCs under the Windows XP operating system. It is supported by a very effective graphical interface. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Altomare, A. Cuocci, C. Giacovazzo, C. Moliterni, A. Rizzi, R. 2008-07-16 doi:10.1107/S0021889808016956 International Union of Crystallography QUALX is a new computer program for phase identification using powder diffraction data. Its main features are very effective automation, a user-friendly environment and free availability. en computer programs qualitative analysis powder diffraction data QUALX is a new computer program for phase identification using powder diffraction data. It uses the Powder Diffraction File database, where a search for the phase best matching the experimental powder diffraction pattern is carried out. The program is characterized by a high level of automation: the traditional steps aimed at interpreting the experimental pattern before the search (background estimation, peak search, peak intensity evaluation) are executed automatically. The search may be carried out via constraints on compound name and/or chemical elements. In addition, several graphical options requested interactively enable the user to perform zero point correction evaluation, Kα2 stripping and smoothing. The program, written in Fortran95 and C++, runs on PCs under the Windows XP operating system. It is supported by a very effective graphical interface. text/html QUALX: a computer program for qualitative analysis using powder diffraction data text 4 41 2008-07-16 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography computer programs 815 817 http://scripts.iucr.org/cgi-bin/paper?dd5038 A fast search method for X-ray Bragg reflexes of misoriented crystals is presented. The method is also applicable to determine the accuracy of the crystal orientation. This technique is demonstrated by means of a simple setup for Berg–Barrett X-ray topography, consisting of a rotating sample holder on a two-circle diffractometer. The imaged area of the topograms is about 1 cm2, and the quality is comparable to the topograms taken by white-beam synchrotron X-ray topography. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Andreas, B. Kuetgens, U. Becker, P. 2008-06-14 doi:10.1107/S0021889808015999 International Union of Crystallography A fast search method for Bragg reflexes of misoriented crystals in Berg–Barrett topography is presented. en X-ray topography (XRT) Berg–Barrett sapphire crystal dislocation A fast search method for X-ray Bragg reflexes of misoriented crystals is presented. The method is also applicable to determine the accuracy of the crystal orientation. This technique is demonstrated by means of a simple setup for Berg–Barrett X-ray topography, consisting of a rotating sample holder on a two-circle diffractometer. The imaged area of the topograms is about 1 cm2, and the quality is comparable to the topograms taken by white-beam synchrotron X-ray topography. text/html Fast and easy Bragg reflex search for Berg–Barrett topography of misoriented crystals text 4 41 2008-06-14 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography laboratory notes 818 821 http://scripts.iucr.org/cgi-bin/paper?aj5113 A compact reaction cell is described for in-situ experiments requiring control of both the temperature of the sample and the atmosphere over the sample. The cell incorporates an optional furnace capable of temperatures of up to ∼1273 K. The compact design and ability of the cell to mount directly on a standard goniometer head allows portability to a large number of diffraction instruments at synchrotron sources. Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Chupas, P.J. Chapman, K.W. Kurtz, C. Hanson, J.C. Lee, P.L. Grey, C.P. 2008-07-16 doi:10.1107/S0021889808020165 International Union of Crystallography A versatile and compact flow-cell/furnace that enables control of the sample atmosphere and temperature for in-situ X-ray scattering experiments is described. en flow-cells furnaces X-ray scattering non-ambient conditions in-situ diffraction A compact reaction cell is described for in-situ experiments requiring control of both the temperature of the sample and the atmosphere over the sample. The cell incorporates an optional furnace capable of temperatures of up to ∼1273 K. The compact design and ability of the cell to mount directly on a standard goniometer head allows portability to a large number of diffraction instruments at synchrotron sources. text/html A versatile sample-environment cell for non-ambient X-ray scattering experiments text 4 41 2008-07-16 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography laboratory notes 822 824 http://scripts.iucr.org/cgi-bin/paper?es0364 Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Moore, M. 2008-07-16 doi:10.1107/S0021889808020712 International Union of Crystallography en text/html Andrew Richard Lang (1924–2008) text 4 41 2008-07-16 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography crystallographers 825 825 http://scripts.iucr.org/cgi-bin/paper?pf0067 Copyright (c) 2008 International Union of Crystallography urn:issn:0021-8898 Chateigner, D. 2008-06-14 doi:10.1107/S0021889808015987 International Union of Crystallography en book review text/html X-ray diffraction by polycrystalline materials. By René Guinebretière. Pp. 351. London: ISTE, 2007. Price (hardcover) EUR 124.83. ISBN 978-1905209217. text 4 41 2008-06-14 Copyright (c) 2008 International Union of Crystallography Journal of Applied Crystallography book reviews 826 827