Foundations of Crystallography

 

Acta Cryst. (2000). A56, 1  [ doi:10.1107/S0108767399015871 ]

New developments for Acta Crystallographica Section A

A. Authier

Synopsis: Editorial for 2000.

Online January 2000

 

Acta Cryst. (2000). A56, 2-10  [ doi:10.1107/S0108767399010211 ]

Resonant X-ray scattering in the presence of several anisotropic factors

E. N. Ovchinnikova and V. E. Dmitrienko

Synopsis: The general form of the resonant part of the X-ray susceptibility tensor near absorption edges is found when there are several anisotropic factors in a crystal. The simultaneous existence of anisotropy of local atomic environment, magnetic ordering and orbital ordering is considered in detail.

Online January 2000

 

Acta Cryst. (2000). A56, 11-14  [ doi:10.1107/S0108767399010478 ]

Diffraction analysis of decorated Fibonacci chains in the average unit-cell approach

J. Wolny and L. Pytlik

Synopsis: A novel approach to diffraction analysis of decorated quasicrystals is discussed. An average unit cell has been constructed for a decorated Fibonacci chain and used for analysis of its diffraction pattern.

Online January 2000

 

Acta Cryst. (2000). A56, 15-23  [ doi:10.1107/S0108767399009137 ]

Minimal surfaces with self-intersections along straight lines. II. Surfaces forming three-periodic labyrinths

E. Koch

Synopsis: Minimal surfaces with straight self-intersections may subdivide R³ into two, four or eight three-periodic labyrinths. The properties of such surfaces (three orientable and 44 non-orientable ones) are described.

Online January 2000

 

Acta Cryst. (2000). A56, 24-28  [ doi:10.1107/S0108767399011009 ]

Atoms in crystals - from experimental charge densities

C. Flensburg and D. Madsen

Synopsis: The atoms in crystals partitioning scheme of the electron density has been implemented in the program VALRAY and some examples of integrated atomic properties are given using two recent charge-density studies.

Online January 2000

 

Acta Cryst. (2000). A56, 29-35  [ doi:10.1107/S0108767399009605 ]

Structures of nanometre-size crystals determined from selected-area electron diffraction data

T. E. Weirich, X. D. Zou, R. Ramlau, A. Simon, G. L. Cascarano, C. Giacovazzo and S. Hovmöller

Synopsis: The structures of a new modification of Ti₂Se and several related metal-rich compounds were solved from selected-area electron diffraction data using quasi-automatic direct methods.

Online January 2000

 

Acta Cryst. (2000). A56, 36-48  [ doi:10.1107/S010876739901048X ]

The arithmetic symmetry of monoatomic 2-nets

G. Fadda and G. Zanzotto

Synopsis: It is well known that there exist five arithmetic (Bravais) types of 1-nets (two-dimensional simple lattices). We show that there exist also five distinct arithmetic types of monoatomic 2-nets (two-dimensional lattices with two identical points on their unit cell).

Online January 2000

 

Acta Cryst. (2000). A56, 49-61  [ doi:10.1107/S0108767399010533 ]

Icosahedral quasiperiodic packing of fibres parallel to fivefold and threefold axes

M. Audier and M. Duneau

Synopsis: Building rules are determined for icosahedral quasiperiodic packings of fibres of circular cross section whose axes are parallel to either threefold icosahedral axes or both fivefold and threefold icosahedral axes.

Online January 2000

 

Acta Cryst. (2000). A56, 62-67  [ doi:10.1107/S0108767399010818 ]

Prospects for kinematical least-squares refinement in polymer electron crystallography

D. L. Dorset and C. J. Gilmore

Synopsis: Electron diffraction intensities from poly(1-butene) are the basis for least-squares structure refinement. With soft constraints placed on bond lengths, an improved structural model can be obtained, despite multiple-scattering perturbations.

Online January 2000

 

Acta Cryst. (2000). A56, 68-72  [ doi:10.1107/S0108767399011174 ]

Distribution and interference functions for two-dimensional hexagonal paracrystals

B. Busson and J. Doucet

Synopsis: The distribution and scattering interference functions are calculated for two-dimensional hexagonal paracrystals. This modelling respects the hexagonal symmetry, which is not the case for general modelling.

Online January 2000

 

Acta Cryst. (2000). A56, 73-84  [ doi:10.1107/S0108767399011277 ]

Fixed-scale wavelet-type approximation of periodic density distributions

V. Y. Lunin

Synopsis: Mathematical tools are developed for the decomposition of a distribution in the unit cell into a weighted sum of shifted copies of the same function chosen in advance.

Online January 2000

 

Acta Cryst. (2000). A56, 85-91  [ doi:10.1107/S0108767399005838 ]

Microdomain model analysis on the negative partial intensity in a disordered ternary alloy

S. Hashimoto

Synopsis: Short-range ordering in a ternary alloy is discussed according to the ordered microdomain model. The negative X-ray partial intensity can be explained by a mixing occupation of different atoms on the sublattice of the ordered lattice.

Online January 2000

 

Acta Cryst. (2000). A56, 92-95  [ doi:10.1107/S0108767399012830 ]

Double crystals

B. Wecht, M. Barber and J. Tice

Synopsis: An explanation and proof are given of the different kinds of cost-minimizing planar double crystals that can occur, assuming an interface that carries a fraction of the energy (per unit length) of the faces.

Online January 2000

 

Acta Cryst. (2000). A56, 96-98  [ doi:10.1107/S0108767399012283 ]

Symmetry Elements in Space Groups and Point Groups. Addenda to two IUCr Reports on the Nomenclature of Symmetry

H. D. Flack, H. Wondratschek, T. Hahn and S. C. Abrahams

Synopsis: An ambiguity in the definition of `symmetry element' is removed by redefining the `geometric element'. A revised diagram of glide-plane aspects is presented that contains three more than the 15 illustrated previously.

Online January 2000

 

Acta Cryst. (2000). A56, 99-103  [ doi:10.1107/S0108767399011435 ]

Notes for Authors

Online January 2000