Acta Crystallographica Section A
//journals.iucr.org/a/issues/2018/06/00/isscontsbdy.html
Acta Crystallographica Section A: Foundations and Advances covers theoretical and fundamental aspects of the structure of matter. The journal is the prime forum for research in diffraction physics and the theory of crystallographic structure determination by diffraction methods using X-rays, neutrons and electrons. The structures include periodic and aperiodic crystals, and non-periodic disordered materials, and the corresponding Bragg, satellite and diffuse scattering, thermal motion and symmetry aspects. Spatial resolutions range from the subatomic domain in charge-density studies to nanodimensional imperfections such as dislocations and twin walls. The chemistry encompasses metals, alloys, and inorganic, organic and biological materials. Structure prediction and properties such as the theory of phase transformations are also covered.enCopyright (c) 2018 International Union of Crystallography2018-10-30International Union of CrystallographyInternational Union of Crystallographyhttp://journals.iucr.orgurn:issn:2053-2733Acta Crystallographica Section A: Foundations and Advances covers theoretical and fundamental aspects of the structure of matter. The journal is the prime forum for research in diffraction physics and the theory of crystallographic structure determination by diffraction methods using X-rays, neutrons and electrons. The structures include periodic and aperiodic crystals, and non-periodic disordered materials, and the corresponding Bragg, satellite and diffuse scattering, thermal motion and symmetry aspects. Spatial resolutions range from the subatomic domain in charge-density studies to nanodimensional imperfections such as dislocations and twin walls. The chemistry encompasses metals, alloys, and inorganic, organic and biological materials. Structure prediction and properties such as the theory of phase transformations are also covered.text/htmlActa Crystallographica Section A: Foundations and Advances, Volume 74, Part 6, 2018textweekly62002-01-01T00:00+00:006742018-10-30Copyright (c) 2018 International Union of CrystallographyActa Crystallographica Section A: Foundations and Advances616urn:issn:2053-2733med@iucr.orgOctober 20182018-10-30Acta Crystallographica Section Ahttp://journals.iucr.org/logos/rss10a.gif
//journals.iucr.org/a/issues/2018/06/00/isscontsbdy.html
Still imageOn the origin of crystallinity: a lower bound for the regularity radius of Delone sets
http://scripts.iucr.org/cgi-bin/paper?eo5086
The mathematical conditions for the origin of long-range order or crystallinity in ideal crystals are one of the very fundamental problems of modern crystallography. It is widely believed that the (global) regularity of crystals is a consequence of `local order', in particular the repetition of local fragments, but the exact mathematical theory of this phenomenon is poorly known. In particular, most mathematical models for quasicrystals, for example Penrose tiling, have repetitive local fragments, but are not (globally) regular. The universal abstract models of any atomic arrangements are Delone sets, which are uniformly distributed discrete point sets in Euclidean d space. An ideal crystal is a regular or multi-regular system, that is, a Delone set, which is the orbit of a single point or finitely many points under a crystallographic group of isometries. The local theory of regular or multi-regular systems aims at finding sufficient local conditions for a Delone set X to be a regular or multi-regular system. One of the main goals is to estimate the regularity radius \hat{\rho}_d for Delone sets X in terms of the radius R of the largest `empty ball' for X. The celebrated `local criterion for regular systems' provides an upper bound for \hat{\rho_d} for any d. Better upper bounds are known for d ≤ 3. The present article establishes the lower bound \hat{\rho_d}\geq 2dR for all d, which is linear in d. The best previously known lower bound had been \hat{\rho}_d\geq 4R for d ≥ 2. The proof of the new lower bound is accomplished through explicit constructions of Delone sets with mutually equivalent (2dR − ∊)-clusters, which are not regular systems. The two- and three-dimensional constructions are illustrated by examples. In addition to its fundamental importance, the obtained result is also relevant for the understanding of geometrical conditions of the formation of ordered and disordered arrangements in polytypic materials.Copyright (c) 2018 International Union of Crystallographyurn:issn:2053-2733Baburin, I.A.Bouniaev, M.Dolbilin, N.Erokhovets, N.Y.Garber, A.Krivovichev, S.V.Schulte, E.2018-10-15doi:10.1107/S2053273318012135International Union of CrystallographyA new lower bound is proved for the regularity radius of a Delone set in dimensions d greater than or equal to 3.ENDelone setsregularity radiuscrystallinityEngel setsThe mathematical conditions for the origin of long-range order or crystallinity in ideal crystals are one of the very fundamental problems of modern crystallography. It is widely believed that the (global) regularity of crystals is a consequence of `local order', in particular the repetition of local fragments, but the exact mathematical theory of this phenomenon is poorly known. In particular, most mathematical models for quasicrystals, for example Penrose tiling, have repetitive local fragments, but are not (globally) regular. The universal abstract models of any atomic arrangements are Delone sets, which are uniformly distributed discrete point sets in Euclidean d space. An ideal crystal is a regular or multi-regular system, that is, a Delone set, which is the orbit of a single point or finitely many points under a crystallographic group of isometries. The local theory of regular or multi-regular systems aims at finding sufficient local conditions for a Delone set X to be a regular or multi-regular system. One of the main goals is to estimate the regularity radius \hat{\rho}_d for Delone sets X in terms of the radius R of the largest `empty ball' for X. The celebrated `local criterion for regular systems' provides an upper bound for \hat{\rho_d} for any d. Better upper bounds are known for d ≤ 3. The present article establishes the lower bound \hat{\rho_d}\geq 2dR for all d, which is linear in d. The best previously known lower bound had been \hat{\rho}_d\geq 4R for d ≥ 2. The proof of the new lower bound is accomplished through explicit constructions of Delone sets with mutually equivalent (2dR − ∊)-clusters, which are not regular systems. The two- and three-dimensional constructions are illustrated by examples. In addition to its fundamental importance, the obtained result is also relevant for the understanding of geometrical conditions of the formation of ordered and disordered arrangements in polytypic materials.text/htmlOn the origin of crystallinity: a lower bound for the regularity radius of Delone setstext6742018-10-15Copyright (c) 2018 International Union of CrystallographyActa Crystallographica Section Aresearch papers616629Blind lattice-parameter determination of cubic and tetragonal phases with high accuracy using a single EBSD pattern
http://scripts.iucr.org/cgi-bin/paper?lk5031
The Bravais lattices and their lattice parameters are blindly determined using electron backscatter diffraction (EBSD) patterns of materials with cubic or tetragonal crystal structures. Since the geometric relationships in a single EBSD pattern are overdetermined, the relative errors of determining the lattice parameters as well as the axial ratios are confined to about 0.7 ± 0.4% and 0.07 ± 0.03%, respectively, for ideal simulated EBSD patterns. The accuracy of the crystal orientation determination reaches about 0.06 ± 0.03°. With careful manual band detection, the accuracy of determining lattice parameters from experimental patterns can be as good as from simulated patterns, although the results from simulated patterns are often better than expermental patterns, which are lower quality and contain uncertain systematic errors. The reasonably high accuracy is obtained primarily because the detection of the diffracting-plane traces and zone axes is relatively accurate. The results here demonstrate that the developed procedure based on the EBSD technique presents a reliable tool for crystallographic characterization of the Bravais lattices of unknown phases.Copyright (c) 2018 International Union of Crystallographyurn:issn:2053-2733Han, M.Chen, C.Zhao, G.Li, L.Nolze, G.Yu, B.Huang, X.Zhu, Y.2018-10-04doi:10.1107/S2053273318010963International Union of CrystallographyA reliable method which can accurately derive the Bravais-lattice type and lattice parameters of unknown phases from a single EBSD pattern without a priori knowledge is proposed. By solving the geometric relationships in an EBSD pattern based on a huge overdetermined system of equations, error accumulation can be avoided, with the relative errors confined to ∼1% for lattice parameters, <0.4% for axial ratios and ∼0.1° for crystal orientation.ENelectron backscatter diffractionEBSDBravais latticeslattice parametersKikuchi patternsThe Bravais lattices and their lattice parameters are blindly determined using electron backscatter diffraction (EBSD) patterns of materials with cubic or tetragonal crystal structures. Since the geometric relationships in a single EBSD pattern are overdetermined, the relative errors of determining the lattice parameters as well as the axial ratios are confined to about 0.7 ± 0.4% and 0.07 ± 0.03%, respectively, for ideal simulated EBSD patterns. The accuracy of the crystal orientation determination reaches about 0.06 ± 0.03°. With careful manual band detection, the accuracy of determining lattice parameters from experimental patterns can be as good as from simulated patterns, although the results from simulated patterns are often better than expermental patterns, which are lower quality and contain uncertain systematic errors. The reasonably high accuracy is obtained primarily because the detection of the diffracting-plane traces and zone axes is relatively accurate. The results here demonstrate that the developed procedure based on the EBSD technique presents a reliable tool for crystallographic characterization of the Bravais lattices of unknown phases.text/htmlBlind lattice-parameter determination of cubic and tetragonal phases with high accuracy using a single EBSD patterntext6742018-10-04Copyright (c) 2018 International Union of CrystallographyActa Crystallographica Section Aresearch papers630639Simulating the diffraction line profile from nanocrystalline powders using a spherical harmonics expansion
http://scripts.iucr.org/cgi-bin/paper?ib5062
An accurate description of the diffraction line profile from nanocrystalline powders can be obtained by a spherical harmonics expansion of the profile function. The procedure outlined in this work is found to be computationally efficient and applicable to the line profile for any crystallite shape and size. Practical examples of the diffraction pattern peak profiles resulting from cubic crystallites between 1 and 100 nm in size are shown.Copyright (c) 2018 International Union of Crystallographyurn:issn:2053-2733Beyerlein, K.R.Scardi, P.2018-10-04doi:10.1107/S2053273318011452International Union of CrystallographyA spherical harmonics expansion is proposed to model the diffraction line profile from nanocrystalline powders. The procedure is computationally efficient and applicable to any crystallite shape and size.ENline profile analysisnanocrystalline materialspowder diffractiondomain size broadeningAn accurate description of the diffraction line profile from nanocrystalline powders can be obtained by a spherical harmonics expansion of the profile function. The procedure outlined in this work is found to be computationally efficient and applicable to the line profile for any crystallite shape and size. Practical examples of the diffraction pattern peak profiles resulting from cubic crystallites between 1 and 100 nm in size are shown.text/htmlSimulating the diffraction line profile from nanocrystalline powders using a spherical harmonics expansiontext6742018-10-04Copyright (c) 2018 International Union of CrystallographyActa Crystallographica Section Aresearch papers640646Atomic scale analyses of {\bb Z}-module defects in an NiZr alloy
http://scripts.iucr.org/cgi-bin/paper?td5054
Some specific structures of intermetallic alloys, like approximants of quasicrystals, have their unit cells and most of their atoms located on a periodic fraction of the nodes of a unique {\bb Z}-module [a set of the irrational projections of the nodes of a (N > 3-dimensional) lattice]. Those hidden internal symmetries generate possible new kinds of defects like coherent twins, translation defects and so-called module dislocations that have already been discussed elsewhere [Quiquandon et al. (2016). Acta Cryst. A72, 55–61; Sirindil et al. (2017). Acta Cryst. A73, 427–437]. Presented here are electron microscopy observations of the orthorhombic phase NiZr – and its low-temperature monoclinic variant – which reveal the existence of such defects based on the underlying {\bb Z}-module generated by the five vertices of the regular pentagon. New high-resolution electron microscopy (HREM) and scanning transmission electron microscopy high-angle annular dark-field (STEM-HAADF) observations demonstrate the agreement between the geometrical description of the structure in five dimensions and the experimental observations of fivefold twins and translation defects.Copyright (c) 2018 Abdullah Sirindil et al.urn:issn:2053-2733Sirindil, A.Kobold, R.Mompiou, F.Lartigue-Korinek, S.Perriere, L.Patriarche, G.Quiquandon, M.Gratias, D.2018-10-04doi:10.1107/S2053273318011439International Union of CrystallographyThis article describes the observation and determination of {\bb Z}-module defects (twins, translation faults and module dislocations) in NiZr by high-resolution electron microscopy (HREM), and scanning transmission electron microscopy bright-field (STEM-BF) and high-angle annular dark-field (STEM-HAADF).EN{\bb Z}-moduledefectstwinsdislocationsHREM-HAADFSome specific structures of intermetallic alloys, like approximants of quasicrystals, have their unit cells and most of their atoms located on a periodic fraction of the nodes of a unique {\bb Z}-module [a set of the irrational projections of the nodes of a (N > 3-dimensional) lattice]. Those hidden internal symmetries generate possible new kinds of defects like coherent twins, translation defects and so-called module dislocations that have already been discussed elsewhere [Quiquandon et al. (2016). Acta Cryst. A72, 55–61; Sirindil et al. (2017). Acta Cryst. A73, 427–437]. Presented here are electron microscopy observations of the orthorhombic phase NiZr – and its low-temperature monoclinic variant – which reveal the existence of such defects based on the underlying {\bb Z}-module generated by the five vertices of the regular pentagon. New high-resolution electron microscopy (HREM) and scanning transmission electron microscopy high-angle annular dark-field (STEM-HAADF) observations demonstrate the agreement between the geometrical description of the structure in five dimensions and the experimental observations of fivefold twins and translation defects.text/htmlAtomic scale analyses of {\bb Z}-module defects in an NiZr alloytext6742018-10-04Copyright (c) 2018 Abdullah Sirindil et al.Acta Crystallographica Section Aresearch papers647658A tenfold twin of the CrB structure type
http://scripts.iucr.org/cgi-bin/paper?sc5123
NiZr crystallized from an amorphous matrix or solidified from an undercooled melt exhibits a tenfold twinned microstructure, which is explained by an ideal twin model utilizing special geometric properties of the CrB structure type. The model is unique in several ways: (i) it contains no adjustable parameters other than a scaling factor accounting for the smallest interatomic distance; (ii) it features an irrational shift in the translational part of the twin operation; and (iii) it has many traits commonly observed for quasicrystals, connected to the occurrence of decagonal long-range orientational order, making NiZr the first experimental example of the recently introduced concept of {\bb Z}-module twinning. It is shown how these remarkable properties of the tenfold twin's structure model are related to one another and founded in number theory as well as in the mathematical theory of aperiodic order.Copyright (c) 2018 International Union of Crystallographyurn:issn:2053-2733Hornfeck, W.2018-10-04doi:10.1107/S2053273318011828International Union of CrystallographyThe structure of the tenfold twins formed by CrB-type NiZr is explained by an idealization of the NiZr crystal structure, involving atoms occupying the nodes of a pentagonal {\bb Z}-module, and the chiral twin structure being parameterized by a spiral generating formula.ENtwinningspiral growthintermetallicsdecagonal symmetryaperiodic crystalsNiZr crystallized from an amorphous matrix or solidified from an undercooled melt exhibits a tenfold twinned microstructure, which is explained by an ideal twin model utilizing special geometric properties of the CrB structure type. The model is unique in several ways: (i) it contains no adjustable parameters other than a scaling factor accounting for the smallest interatomic distance; (ii) it features an irrational shift in the translational part of the twin operation; and (iii) it has many traits commonly observed for quasicrystals, connected to the occurrence of decagonal long-range orientational order, making NiZr the first experimental example of the recently introduced concept of {\bb Z}-module twinning. It is shown how these remarkable properties of the tenfold twin's structure model are related to one another and founded in number theory as well as in the mathematical theory of aperiodic order.text/htmlA tenfold twin of the CrB structure typetext6742018-10-04Copyright (c) 2018 International Union of CrystallographyActa Crystallographica Section Aresearch papers659672An accurate theory of X-ray coplanar multiple SRMS diffractometry
http://scripts.iucr.org/cgi-bin/paper?lk5033
The article reports an accurate theory of X-ray coplanar multiple diffraction for an experimental setup that consists of a generic synchrotron radiation (SR) source, double-crystal monochromator (M) and slit (S). It is called for brevity the theory of X-ray coplanar multiple SRMS diffractometry. The theory takes into account the properties of synchrotron radiation as well as the features of diffraction of radiation in the monochromator crystals and the slit. It is shown that the angular and energy dependence (AED) of the sample reflectivity registered by a detector has the form of a convolution of the AED in the case of the monochromatic plane wave with the instrumental function which describes the angular and energy spectrum of radiation incident on the sample crystal. It is shown that such a scheme allows one to measure the rocking curves close to the case of the monochromatic incident plane wave, but only using the high-order reflections by monochromator crystals. The case of four-beam (220)(331)({\overline {11}}1) diffraction in Si is considered in detail.Copyright (c) 2018 International Union of Crystallographyurn:issn:2053-2733Kohn, V.G.2018-10-04doi:10.1107/S2053273318012615International Union of CrystallographyAn accurate theory of X-ray coplanar multiple diffraction in an experimental setup that consists of a synchrotron radiation (SR) source, double-crystal monochromator (M) and slit (S), in brief the theory of coplanar multiple SRMS diffractometry, is reported. It is shown that such a setup allows one to measure the rocking curves close to the case of the monochromatic incident plane wave with high-order reflections by monochromator crystals.ENX-ray diffractionsilicon crystalmultiple diffractionsynchrotron radiationslit diffractionThe article reports an accurate theory of X-ray coplanar multiple diffraction for an experimental setup that consists of a generic synchrotron radiation (SR) source, double-crystal monochromator (M) and slit (S). It is called for brevity the theory of X-ray coplanar multiple SRMS diffractometry. The theory takes into account the properties of synchrotron radiation as well as the features of diffraction of radiation in the monochromator crystals and the slit. It is shown that the angular and energy dependence (AED) of the sample reflectivity registered by a detector has the form of a convolution of the AED in the case of the monochromatic plane wave with the instrumental function which describes the angular and energy spectrum of radiation incident on the sample crystal. It is shown that such a scheme allows one to measure the rocking curves close to the case of the monochromatic incident plane wave, but only using the high-order reflections by monochromator crystals. The case of four-beam (220)(331)({\overline {11}}1) diffraction in Si is considered in detail.text/htmlAn accurate theory of X-ray coplanar multiple SRMS diffractometrytext6742018-10-04Copyright (c) 2018 International Union of CrystallographyActa Crystallographica Section Aresearch papers673680Intensity distribution profile of double Bragg scattering in the small-angle region from highly oriented pyrolytic graphite
http://scripts.iucr.org/cgi-bin/paper?wo5027
It is observed that radial streak patterns of double Bragg scattering appear in the small-angle X-ray scattering from highly oriented pyrolytic graphite (HOPG). The intensity profile of double Bragg scattering from an HOPG sample is calculated theoretically. Assuming that the c axes of the graphite crystallites in the HOPG sample are distributed around an orientation vector and their distribution function has a Gaussian form, it is found that the intensity profile of double Bragg scattering is expressed by a double Gaussian function of the scattering angle and the azimuthal angle of the streak. The calculated intensity profile is compared with the experimental one. The method developed in this article can be used to estimate the orientational distribution of crystallites in uniaxial polycrystalline materials.Copyright (c) 2018 International Union of Crystallographyurn:issn:2053-2733Ohmasa, Y.Chiba, A.2018-10-12doi:10.1107/S2053273318012469International Union of CrystallographyThe intensity profile of double Bragg scattering from uniaxial polycrystalline materials, such as highly oriented pyrolytic graphite (HOPG), is calculated theoretically and compared with that observed experimentally. The intensity profile is related to the orientational distribution of crystallites.ENdouble Bragg scatteringsmall-angle X-ray scatteringhighly oriented pyrolytic graphiteHOPGintensity profilesIt is observed that radial streak patterns of double Bragg scattering appear in the small-angle X-ray scattering from highly oriented pyrolytic graphite (HOPG). The intensity profile of double Bragg scattering from an HOPG sample is calculated theoretically. Assuming that the c axes of the graphite crystallites in the HOPG sample are distributed around an orientation vector and their distribution function has a Gaussian form, it is found that the intensity profile of double Bragg scattering is expressed by a double Gaussian function of the scattering angle and the azimuthal angle of the streak. The calculated intensity profile is compared with the experimental one. The method developed in this article can be used to estimate the orientational distribution of crystallites in uniaxial polycrystalline materials.text/htmlIntensity distribution profile of double Bragg scattering in the small-angle region from highly oriented pyrolytic graphitetext6742018-10-12Copyright (c) 2018 International Union of CrystallographyActa Crystallographica Section Aresearch papers681698Computer simulations of X-ray spherical wave dynamical diffraction in one and two crystals in the Laue case
http://scripts.iucr.org/cgi-bin/paper?lk5036
This article reports computer simulations of X-ray spherical wave dynamical diffraction in one and two single crystals in the Laue case. An X-ray compound refractive lens (CRL) as a secondary radiation source of spherical waves was considered for the first time and in contrast to previous simulations with the assumption of the use of a slit. The main properties of the CRL as a secondary source are discussed and two focusing phenomena are analysed. The first one is the diffraction focusing effect for one single crystal in the reflected beam and in the case of a large source-to-detector distance. The second one is the same but for two single crystals and for the twice-reflected beam in the case of a short distance between the source and detector. The first effect is well pronounced in the case of strong absorption. However, it may also be used as an element of an energy spectrometer in the medium and even weak absorption case. The second effect will appear in the case of weak absorption. It is shown that it is not effective to use it in an energy spectrometer. In the case of weak absorption the transverse size of the diffraction focused beam will oscillate together with the reflected beam integral intensity. The oscillation period is close to the extinction length.Copyright (c) 2018 International Union of Crystallographyurn:issn:2053-2733Kohn, V.G.Smirnova, I.A.2018-10-12doi:10.1107/S2053273318012627International Union of CrystallographyComputer simulations of X-ray spherical wave dynamical diffraction in one and two crystals in the Laue case are reported. A spherical wave is created by an X-ray compound refractive lens. Diffraction focusing phenomena in one crystal and for the reflected beam, as well as in two crystals and for the twice-reflected beam, are simulated and discussed. How these phenomena may be used in an energy spectrometer is investigated.ENX-ray diffractiondiffraction focusingcompound refractive lenssynchrotron radiationXFEL energy spectrometerThis article reports computer simulations of X-ray spherical wave dynamical diffraction in one and two single crystals in the Laue case. An X-ray compound refractive lens (CRL) as a secondary radiation source of spherical waves was considered for the first time and in contrast to previous simulations with the assumption of the use of a slit. The main properties of the CRL as a secondary source are discussed and two focusing phenomena are analysed. The first one is the diffraction focusing effect for one single crystal in the reflected beam and in the case of a large source-to-detector distance. The second one is the same but for two single crystals and for the twice-reflected beam in the case of a short distance between the source and detector. The first effect is well pronounced in the case of strong absorption. However, it may also be used as an element of an energy spectrometer in the medium and even weak absorption case. The second effect will appear in the case of weak absorption. It is shown that it is not effective to use it in an energy spectrometer. In the case of weak absorption the transverse size of the diffraction focused beam will oscillate together with the reflected beam integral intensity. The oscillation period is close to the extinction length.text/htmlComputer simulations of X-ray spherical wave dynamical diffraction in one and two crystals in the Laue casetext6742018-10-12Copyright (c) 2018 International Union of CrystallographyActa Crystallographica Section Aresearch papers699704Crystal symmetry aspects of materials with magnetic spin reorientation
http://scripts.iucr.org/cgi-bin/paper?sc5124
The symmetry of materials which undergo a continuous spin reorientation has been analysed. It is shown that continuous spin reorientation is possible only in materials with triclinic or monoclinic crystal structure symmetry, i.e. other symmetries – orthorhombic, tetragonal, trigonal, hexagonal and cubic – are forbidden.Copyright (c) 2018 International Union of Crystallographyurn:issn:2053-2733Przeniosło, R.Fabrykiewicz, P.Sosnowska, I.2018-10-15doi:10.1107/S2053273318012822International Union of CrystallographyThe symmetry of materials which undergo a continuous spin reorientation can be only triclinic or monoclinic.ENspin reorientationmagnetic orderingmagnetic space groupssymmetryneutron diffractionX-ray diffractionPr3Ru4Al12Mn2S3TbCo3B2α-Fe2O3haematiteThe symmetry of materials which undergo a continuous spin reorientation has been analysed. It is shown that continuous spin reorientation is possible only in materials with triclinic or monoclinic crystal structure symmetry, i.e. other symmetries – orthorhombic, tetragonal, trigonal, hexagonal and cubic – are forbidden.text/htmlCrystal symmetry aspects of materials with magnetic spin reorientationtext6742018-10-15Copyright (c) 2018 International Union of CrystallographyActa Crystallographica Section Aresearch papers705708Ab initio structure determination of nanocrystals of organic pharmaceutical compounds by electron diffraction at room temperature using a Timepix quantum area direct electron detector. Corrigendum
http://scripts.iucr.org/cgi-bin/paper?td9026
Corrections are made to Table 1 in the article by van Genderen et al. [Acta Cryst. (2016), A72, 236–242].Copyright (c) 2018 E. van Genderen et al.urn:issn:2053-2733van Genderen, E.Clabbers, M.T.B.Das, P.P.Stewart, A.Nederlof, I.Barentsen, K.C.Portillo, Q.Pannu, N.S.Nicolopoulos, S.Gruene, T.Abrahams, J.P.2018-10-30doi:10.1107/S2053273318014079International Union of CrystallographyA correction is made to the article by van Genderen et al. [Acta Cryst. (2016), A72, 236–242].ENelectron nanocrystallographyTimepix quantum area detectorcarbamazepinenicotinic acidelectron diffraction structure determinationCorrections are made to Table 1 in the article by van Genderen et al. [Acta Cryst. (2016), A72, 236–242].text/htmlAb initio structure determination of nanocrystals of organic pharmaceutical compounds by electron diffraction at room temperature using a Timepix quantum area direct electron detector. Corrigendumtext6742018-10-30Copyright (c) 2018 E. van Genderen et al.Acta Crystallographica Section Aaddenda and errata709709Prices of IUCr journals
http://scripts.iucr.org/cgi-bin/paper?es5006
Copyright (c) 2018 International Union of Crystallographyurn:issn:2053-2733Ashcroft, A.T.2018-10-30doi:10.1107/S2053273318014699International Union of CrystallographyENprices of journalstext/htmlPrices of IUCr journalstext6742018-10-30Copyright (c) 2018 International Union of CrystallographyActa Crystallographica Section Ainternational union of crystallography710711Aperiodic Crystals. From Modulated Phases to Quasicrystals: Structure and Properties. Second edition. By Ted Janssen, Gervais Chapuis and Marc de Boissieu. Oxford University Press, 2018. Pp. 560. Price GBP 45.00 (paperback). ISBN 9780198824442.
http://scripts.iucr.org/cgi-bin/paper?xo0125
Copyright (c) 2018 International Union of Crystallographyurn:issn:2053-2733Steurer, W.2018-10-04doi:10.1107/S2053273318012032International Union of CrystallographyENbook reviewsaperiodic crystalsmodulated phasesquasicrystalstext/htmlAperiodic Crystals. From Modulated Phases to Quasicrystals: Structure and Properties. Second edition. By Ted Janssen, Gervais Chapuis and Marc de Boissieu. Oxford University Press, 2018. Pp. 560. Price GBP 45.00 (paperback). ISBN 9780198824442.text6742018-10-04Copyright (c) 2018 International Union of CrystallographyActa Crystallographica Section Abook reviews712713