Key points are not available for this paper at this time.
Beamline 4-2 at the Stanford Synchrotron Radiation Laboratory is a small-angle X-ray scattering/diffraction facility dedicated to structural studies on mostly noncrystalline biological systems. The instrument consists of a pinhole camera, which covers the magnitude of the scattering vector Q in the range 0.004–1.3 Å−1 Q = (4π/λ)sin θ, where θ and λ are one half of the scattering angle and the X-ray wavelength, respectively, and a Bonse–Hart geometry ultra-small-angle X-ray scattering setup for the Q range an order of magnitude smaller. The pinhole camera allows quick automated distance and detector selection among any combination of five distances and three position-sensitive detectors. The double-crystal monochromator can have either Si 111 crystals or a pair of synthetic multilayer diffractive elements for higher flux applications. We have adopted a suite of software originally developed for macromolecular crystallography for integrated beamline control as well as static and slow time-resolved small-angle scattering data collection. This article outlines recent technological developments and specialized instrumentation for conducting noncrystalline scattering experiments in structural biology at improved time and spatial resolutions.
Smolsky et al. (Sat,) studied this question.