Relativistic X-ray Elastic Scattering Factors for Neutral Atoms Z = 1–54 from Multiconfiguration Dirac–Fock Wavefunctions in the 0–12Å⁻¹ sinθ /λ Range, and Six-Gaussian Analytical Expressions in the 0–6Å⁻¹ Range

X-ray elastic scattering factors for ground-state neutral atoms (H through Xe) have been calculated from the relativistic multiconfiguration Dirac–Fock wavefunctions. The results have been fitted to six-Gaussian analytical expressions for the sinθ/λ ranges of 0–2, 2–4 and 4–6Å⁻¹. The atomic energies and second moments are also presented.

The Optical Activity of Crystalline L-Aspartic Acid

All the components of gyration tensor and birefringence of L-aspartic acid have been successfully measured as a function of the temperature. It is of special interest that the chirality index of aspartic acid was found to be almost the same as that of glutamic acid.

Grain Boundaries as Projections from Higher-Dimensional Lattices

Points of best fit between pairs of lattices are found using higher-dimensional lattices. It constitutes a generalization of the coincidence lattice.

Application of Grazing-Angle X-ray Standing Waves to the In-Plane Structure of a 100Å-Thick Epilayer Film

Dynamical diffraction in an epilayer crystal, as thin as 100Å, is shown to modify significantly the field pattern of grazing-angle X-ray standing waves produced by the substrate. The technique is applied to the determination of the registration and the ordering of a Ca_0.39Sr_0.61F₂ epilayer on GaAs (111).

Improving Direct-Methods Phases by Heavy-Atom Information and Solvent Flattening

Phases obtained by direct methods are improved by using information on the heavy-atom structure and a suitable solvent-flattening technique.

The Translation Problem in Molecular Replacement Techniques. II. The Estimate of Quartet Invariants

The probabilistic estimate of quartet invariants is obtained when prior information on well oriented molecular fragments is available.

Alternative formulae for the number of sublattices

Two formulae for the number of sublattices of a given index k of an n-dimensional lattice are presented which give the result in a considerably quicker way than any previous method.

Metric properties of the root-mean-square deviation of vector sets

A proof is given that the root-mean-square deviation between more than two vector sets after optimal superposition induces a metric.

Additional comments on the theoretical formulation of X-ray moiré fringes

A previous theoretical formulation of X-ray moiré fringes for a bicrystal model is explained to clarify the meanings of the formulation.

A detailed observation of the nonprojectiveness of X-ray moiré-fringed diffraction images. Erratum

Erratum to Acta Cryst. (1996), A 52, 312–325.

Report of the Executive Committee for 1996

Prices of IUCr journals

Organic molecular crystals: interaction, localization and transport phenomena by E. A. Silinsh and V. Čápek

Physics and chemistry at oxide surfaces by C. Noguera

Collected works of Dorothy Crowfoot Hodgkin. Vol. I. Insulin. Vol. II. Cholestrol, penicillin and other antibiotics. Vol. III. General crystallography and essays edited by G. G. Dodson, J. P. Glusker, S. Ramaseshan and K. Venkatesan

Synchrotron radiation techniques in industrial, chemical, and materials science edited by K. L. D'Amico, L. J. Terminello and D. K. Shuh

X-ray and neutron dynamical diffraction, theory and applications edited by A. Authier, S. Lagomarsino and B. K. Tanner