The anomalous dispersion corrections for zirconium

A scanning X-ray interferometer was used to measure the forward scattering amplitude for zirconium at a number of wavelengths near the K absorption edge. The precision of previous experiments has usually been limited by lack of knowledge of either the sample density or its shape. These problems have been eliminated by making simultaneous measurements at two X-ray wavelengths. This new measurement algorithm can be applied at any wavelength which is accessible to X-ray interferometers. The X-ray optical constants of elements with $Z\geq 10$ can be determined over the range 0.1 angstrom $<\lambda <5$ angstrom to a precision which is sufficient to rekindle theoretical interest in the subject.