Simple graphs that guide combinatorial materials design

The representation of crystal structures by nets provides a useful framework for thinking about the design of new materials.

Topological features in crystal structures: a quotient graph assisted analysis of underlying nets and their embeddings

Algebraic and surgery techniques are applied to labelled quotient graphs of crystal structures to perform ring analysis and structural decomposition into subperiodic blocks.

Theo Hahn (1928–2016)

Obituary for Theo Hahn.

Aloysio Janner (1928–2016)

Obituary for Aloysio Janner.

Symmetry-adapted digital modeling I. Axial symmetric proteins

Four axial symmetric proteins are analysed on the basis of two lattices, the form lattice and the modelling lattice. The former is a sublattice of the latter.

Symmetry-adapted digital modeling II. The double-helix B-DNA

The positions of phosphorus in B-DNA are analysed by means of a five-dimensional lattice. This gives a one-to-one correspondence between atomic and indexed positions.

Symmetry-adapted digital modeling III. Coarse-grained icosahedral viruses

The positions of the backbone atoms in an icosahedral virus are indexed using a six-dimensional icosahedral lattice and its projection on three-dimensional space.

Formulation of dynamical theory of X-ray diffraction for perfect crystals in the Laue case using the Riemann surface

The dynamical theory for perfect crystals in the Laue case is reformulated using the Riemann surface.

Computer simulations of X-ray six-beam diffraction in a perfect silicon crystal. I

The results of computer simulations of the transmitted-beam intensity distribution are presented for the case of six-beam (000, 220, 242, 044, −224, −202) diffraction of X-rays in a perfect silicon crystal of thickness 1 mm. Both the plane-wave angular dependence and the six-beam section topographs are investigated.

Monoclinic sphere packings. I. Invariant, univariant and bivariant lattice complexes

All homogeneous sphere packings were derived that refer to the invariant, univariant and bivariant lattice complexes with monoclinic symmetry.

On the group-theoretical approach to the study of interpenetrating nets

A general theoretical framework based on group–subgroup and group–supergroup relations is proposed to describe and derive interpenetrating nets.

Vertex-connectivity in periodic graphs and underlying nets of crystal structures

Labelled quotient graphs can be used to analyse vertex-connectivity in periodic graphs and assign a topological class to crystal structures.

The Scherrer equation and the dynamical theory of X-ray diffraction

The maximum crystal size is determined for application of the Scherrer equation.

Multidimensional period doubling structures

Generalization of the period doubling sequence to arbitrary dimension is developed.

Hydrogen-bond-reversal symmetry and its violation in ice nanotubes

For ice nanotubes consisting of stacked n-membered rings, a new type of generalized symmetry and its violation are discussed.

Estimating the difference between structure-factor amplitudes using multivariate Bayesian inference

A Bayesian model which uses a Markov chain Monte Carlo algorithm has been developed to estimate structure-factor amplitude differences.

Report of the Executive Committee for 2014

Molekülsymmetrie und Spektroskopie

Early Days of X-ray Crystallography