Direct phase determination of large macromolecular crystals using three-beam x-ray interference

Abstract

We report for the first time the direct determination of x-ray-reflection phases of a large-unit-cell volume, 350 000 \AA{} $^{3}$, macromolecular crystal using three-beam diffraction. The crystal polarity (enantiomorph) is determined unambiguously from the peak-intensity measurement. Quantitative analysis of phase angle, with a scaling scheme for intensities, is presented.