Forthcoming article in Acta Crystallographica Section A Foundations and Advances
http://journals.iucr.org/a/journalhomepage.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.en-gbCopyright (c) 2015 International Union of CrystallographyInternational Union of CrystallographyInternational Union of Crystallographyhttp://journals.iucr.orgurn:issn:0108-7673Acta 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 Advancestextdaily12002-01-01T00:00+00:00med@iucr.orgActa Crystallographica Section A Foundations and AdvancesCopyright (c) 2015 International Union of Crystallographyurn:issn:0108-7673Forthcoming article in Acta Crystallographica Section A Foundations and Advanceshttp://journals.iucr.org/logos/rss10a.gif
http://journals.iucr.org/a/journalhomepage.html
Still imageTheoretical study of the properties of X-ray diffraction moiré fringes. I
http://journals.iucr.org/a/services/forthcoming.html#td5025
A detailed and comprehensive theoretical description of X-ray diffraction moiré fringes for a bicrystal specimen is given on the basis of a calculation by plane-wave dynamical diffraction theory, where the effect of the Pendellösung intensity oscillation on the moiré pattern is explained in detail.Copyright (c) 2015 International Union of Crystallographyurn:issn:2053-2733Jun-ichi Yoshimuradoi:10.1107/S2053273315004970International Union of CrystallographyA detailed and comprehensive theoretical description of X-ray diffraction moiré fringes for a bicrystal specimen is given on the basis of a calculation by plane-wave dynamical diffraction theory, where the effect of the Pendellösung intensity oscillation on the moiré pattern is explained in detail.enDIFFRACTION MOIRE FRINGES; PENDELLOSUNG OSCILLATION; PHASE JUMP; GAP PHASEA detailed and comprehensive theoretical description of X-ray diffraction moiré fringes for a bicrystal specimen is given on the basis of a calculation by plane-wave dynamical diffraction theory, where the effect of the Pendellösung intensity oscillation on the moiré pattern is explained in detail.text/htmlTheoretical study of the properties of X-ray diffraction moiré fringes. ItextMore statistics on intermetallic compounds – ternary phases
http://journals.iucr.org/a/services/forthcoming.html#eo5046
Ternary intermetallics – 13 026 compounds contained in the database Pearson's Crystal Data – are discussed with respect to their components, structure types and stoichiometries.Copyright (c) 2015 International Union of Crystallographyurn:issn:2053-2733Dshemuchadse and Steurerdoi:10.1107/S2053273315004064International Union of CrystallographyTernary intermetallics – 13 026 compounds contained in the database Pearson's Crystal Data – are discussed with respect to their components, structure types and stoichiometries.enPLEASE PROVIDE FOUR OR FIVE KEYWORDSTernary intermetallics – 13 026 compounds contained in the database Pearson's Crystal Data – are discussed with respect to their components, structure types and stoichiometries.text/htmlMore statistics on intermetallic compounds – ternary phasestextUnique atom hyper-kagome order in Na4Ir3O8 and in low-symmetry spinel modifications
http://journals.iucr.org/a/services/forthcoming.html#kx5039
Group-theoretical and thermodynamic methods of the Landau theory of phase transitions are used to investigate the hyper-kagome atomic order in structures of ordered spinels and a spinel-like Na4Ir3O8 crystal. The existence of hyper-kagome lattices in six types of ordered spinel structures is predicted theoretically.Copyright (c) 2015 International Union of Crystallographyurn:issn:2053-2733V. M. Talanov et al.doi:10.1107/S2053273315003848International Union of CrystallographyGroup-theoretical and thermodynamic methods of the Landau theory of phase transitions are used to investigate the hyper-kagome atomic order in structures of ordered spinels and a spinel-like Na4Ir3O8 crystal. The existence of hyper-kagome lattices in six types of ordered spinel structures is predicted theoretically.enHYPER-KAGOME ORDER; ORDERED SPINELS; ENANTIOMORPHIC MODIFICATIONS; ATOM AND ORBITAL ORDERS; DECAGONSGroup-theoretical and thermodynamic methods of the Landau theory of phase transitions are used to investigate the hyper-kagome atomic order in structures of ordered spinels and a spinel-like Na4Ir3O8 crystal. The existence of hyper-kagome lattices in six types of ordered spinel structures is predicted theoretically.text/htmlUnique atom hyper-kagome order in Na4Ir3O8 and in low-symmetry spinel modificationstextIcosahedral symmetry breaking: C60 to C84, C108 and to related nanotubes
http://journals.iucr.org/a/services/forthcoming.html#kx5040
The structure of a particular type of hollow-cage higher fullerene (C60+N24) is described and their construction explained from a symmetry-breaking mechanism starting from perfect icosahedral symmetry of C60 to specific subgroups A1 × A1. This mechanism expands and completes previous results describing the existence of other groups of fullerenes (C60+N10, C60+N18) based on the breaking of icosahedral symmetry of C60 to the subgroups H2 and A2. The mechanism is extended to describe the cases that generate carbon nanotubes.Copyright (c) 2015 International Union of Crystallographyurn:issn:2053-2733Mark Bodner et al.doi:10.1107/S2053273315003824International Union of CrystallographyThe structure of a particular type of hollow-cage higher fullerene (C60+N24) is described and their construction explained from a symmetry-breaking mechanism starting from perfect icosahedral symmetry of C60 to specific subgroups A1 × A1. This mechanism expands and completes previous results describing the existence of other groups of fullerenes (C60+N10, C60+N18) based on the breaking of icosahedral symmetry of C60 to the subgroups H2 and A2. The mechanism is extended to describe the cases that generate carbon nanotubes.enFINITE COXETER GROUP; SYMMETRY BREAKING; FULLERENES; NANOTUBESThe structure of a particular type of hollow-cage higher fullerene (C60+N24) is described and their construction explained from a symmetry-breaking mechanism starting from perfect icosahedral symmetry of C60 to specific subgroups A1 × A1. This mechanism expands and completes previous results describing the existence of other groups of fullerenes (C60+N10, C60+N18) based on the breaking of icosahedral symmetry of C60 to the subgroups H2 and A2. The mechanism is extended to describe the cases that generate carbon nanotubes.text/htmlIcosahedral symmetry breaking: C60 to C84, C108 and to related nanotubestextDetermination of small crystal structures from a minimum set of diffraction intensities by homotopy continuation
http://journals.iucr.org/a/services/forthcoming.html#sc5087
A method from numerical algebraic geometry, called homotopy continuation, is used to determine small crystal structures of four or fewer atoms directly from a minimum set of diffraction intensities.Copyright (c) 2015 International Union of Crystallographyurn:issn:2053-2733Leggas and Tsodikovdoi:10.1107/S2053273315003551International Union of CrystallographyA method from numerical algebraic geometry, called homotopy continuation, is used to determine small crystal structures of four or fewer atoms directly from a minimum set of diffraction intensities.enDIRECT METHODS; PHASE PROBLEM; ALGEBRAIC GEOMETRY, AMBIGUITYA method from numerical algebraic geometry, called homotopy continuation, is used to determine small crystal structures of four or fewer atoms directly from a minimum set of diffraction intensities.text/htmlDetermination of small crystal structures from a minimum set of diffraction intensities by homotopy continuationtextMagnetic structure determination from the magnetic pair distribution function (mPDF): ground state of MnO
http://journals.iucr.org/a/services/forthcoming.html#vk5003
Combined atomic and magnetic pair distribution function (PDF) refinements have been performed against neutron scattering data from MnO, recovering the expected long-range-ordered antiferromagnetic state and supporting a scenario of monoclinic symmetry on a local length scale of ∼100 Å. This represents the first experimental application of the magnetic PDF method.Copyright (c) 2015 International Union of Crystallographyurn:issn:2053-2733Frandsen and Billingedoi:10.1107/S205327331500306XInternational Union of CrystallographyCombined atomic and magnetic pair distribution function (PDF) refinements have been performed against neutron scattering data from MnO, recovering the expected long-range-ordered antiferromagnetic state and supporting a scenario of monoclinic symmetry on a local length scale of ∼100 Å. This represents the first experimental application of the magnetic PDF method.enPAIR DISTRIBUTION FUNCTION; MAGNETIC PAIR DISTRIBUTION FUNCTION; NEUTRON SCATTERING; MAGNETIC STRUCTURE; LOCAL STRUCTURECombined atomic and magnetic pair distribution function (PDF) refinements have been performed against neutron scattering data from MnO, recovering the expected long-range-ordered antiferromagnetic state and supporting a scenario of monoclinic symmetry on a local length scale of ∼100 Å. This represents the first experimental application of the magnetic PDF method.text/htmlMagnetic structure determination from the magnetic pair distribution function (mPDF): ground state of MnOtextAxial point groups: rank 1, 2, 3 and 4 property tensor tables
http://journals.iucr.org/a/services/forthcoming.html#kx5041
Physical property tensors of materials such as nanotubes or polymers are determined by the material's axial point group. Rank 1, 2, 3 and 4 property tensors are given for a wide variety of tensor types invariant under each point group in all 31 infinite series of axial point groups.Copyright (c) 2015 International Union of Crystallographyurn:issn:2053-2733Daniel B. Litvindoi:10.1107/S2053273315002740International Union of CrystallographyPhysical property tensors of materials such as nanotubes or polymers are determined by the material's axial point group. Rank 1, 2, 3 and 4 property tensors are given for a wide variety of tensor types invariant under each point group in all 31 infinite series of axial point groups.enAXIAL POINT GROUPS; PROPERTY TENSORS; NANOTUBES; MULTIFERROIC HEXAFERRITESPhysical property tensors of materials such as nanotubes or polymers are determined by the material's axial point group. Rank 1, 2, 3 and 4 property tensors are given for a wide variety of tensor types invariant under each point group in all 31 infinite series of axial point groups.text/htmlAxial point groups: rank 1, 2, 3 and 4 property tensor tablestextAbsolute refinement of crystal structures by X-ray phase measurements
http://journals.iucr.org/a/services/forthcoming.html#ae5003
The application of X-ray phase measurements for absolute identification and improvement of atomic model structures is described.Copyright (c) 2015 International Union of Crystallographyurn:issn:2053-2733Sérgio L. Morelhão et al.doi:10.1107/S2053273315002508International Union of CrystallographyThe application of X-ray phase measurements for absolute identification and improvement of atomic model structures is described.enSINGLE CRYSTALS; CHIRALITY; INVARIANT PHASE TRIPLETS; X-RAY DIFFRACTIONThe application of X-ray phase measurements for absolute identification and improvement of atomic model structures is described.text/htmlAbsolute refinement of crystal structures by X-ray phase measurementstextStructure factor for an icosahedral quasicrystal within a statistical approach
http://journals.iucr.org/a/services/forthcoming.html#pc5049
A structure factor for an icosahedral quasicrystal with an arbitrary decoration scheme based on a primitive icosahedral tiling model and a statistical approach is derived. The average unit cell concept is used as an alternative to the commonly used higher-dimensional description.Copyright (c) 2015 International Union of Crystallographyurn:issn:2053-2733Radoslaw Strzalka et al.doi:10.1107/S2053273315001473International Union of CrystallographyA structure factor for an icosahedral quasicrystal with an arbitrary decoration scheme based on a primitive icosahedral tiling model and a statistical approach is derived. The average unit cell concept is used as an alternative to the commonly used higher-dimensional description.enICOSAHEDRAL QUASICRYSTAL; PRIMITIVE ICOSAHEDRAL TILING; AVERAGE UNIT CELL CONCEPT; STATISTICAL APPROACH; HIGHER-DIMENSIONAL ANALYSIS; DIFFRACTION PATTERNA structure factor for an icosahedral quasicrystal with an arbitrary decoration scheme based on a primitive icosahedral tiling model and a statistical approach is derived. The average unit cell concept is used as an alternative to the commonly used higher-dimensional description.text/htmlStructure factor for an icosahedral quasicrystal within a statistical approachtextX-ray investigation of lateral hetero-structures of inversion domains in LiNbO3, KTiOPO4 and KTiOAsO4
http://journals.iucr.org/a/services/forthcoming.html#wo5016
Periodically-poled ferroelectric crystals are studied by observing their superlattice (grating) diffraction profiles with high-resolution X-ray diffraction. In order to successfully model the data, the effects of strain, and sample and beam coherence, must be taken into account.Copyright (c) 2015 International Union of Crystallographyurn:issn:2053-2733Thomas S. Lyford et al.doi:10.1107/S2053273315001503International Union of CrystallographyPeriodically-poled ferroelectric crystals are studied by observing their superlattice (grating) diffraction profiles with high-resolution X-ray diffraction. In order to successfully model the data, the effects of strain, and sample and beam coherence, must be taken into account.enFERROELECTRICS; DIFFRACTION; COHERENCE; SYNCHROTRON RADIATION; GRATINGPeriodically-poled ferroelectric crystals are studied by observing their superlattice (grating) diffraction profiles with high-resolution X-ray diffraction. In order to successfully model the data, the effects of strain, and sample and beam coherence, must be taken into account.text/htmlX-ray investigation of lateral hetero-structures of inversion domains in LiNbO3, KTiOPO4 and KTiOAsO4textSymmetry of semi-reduced lattices
http://journals.iucr.org/a/services/forthcoming.html#sc5085
The characterization of Bravais types is extended according to metrical, algebraic and geometric properties onto a wide class of primitive lattices (including Buerger-reduced and a substantial part of Delaunay-reduced) related to low-restricted semi-reduced descriptions. There are excellent theoretical and practical reasons for looking at crystal lattice symmetry from an entirely new point of view – the combinatorial set of 960 matrices, their semi-reduced lattice context and their geometric properties.Copyright (c) 2015 International Union of Crystallographyurn:issn:2053-2733Kazimierz Stróżdoi:10.1107/S2053273315001096International Union of CrystallographyThe characterization of Bravais types is extended according to metrical, algebraic and geometric properties onto a wide class of primitive lattices (including Buerger-reduced and a substantial part of Delaunay-reduced) related to low-restricted semi-reduced descriptions. There are excellent theoretical and practical reasons for looking at crystal lattice symmetry from an entirely new point of view – the combinatorial set of 960 matrices, their semi-reduced lattice context and their geometric properties.enREDUCED CELL; METRIC SYMMETRY; SYMMETRY MATRIXThe characterization of Bravais types is extended according to metrical, algebraic and geometric properties onto a wide class of primitive lattices (including Buerger-reduced and a substantial part of Delaunay-reduced) related to low-restricted semi-reduced descriptions. There are excellent theoretical and practical reasons for looking at crystal lattice symmetry from an entirely new point of view – the combinatorial set of 960 matrices, their semi-reduced lattice context and their geometric properties.text/htmlSymmetry of semi-reduced latticestext