New avenues in x-ray microbeam experiments

The high brilliance of third-generation synchrotron radiation sources Aallows new applications in x-ray microdiffraction and microsmall-angle scattering. Beam sizes Adown to about one (mu)m are routinely used and sub-(mu)m beam sizes are becoming available. AScanning diffractometry can he used to examine samples like single fibres without the Anecessity for sectioning, as is required for transmission electron scattering experiments. Examples Aare taken principally from weakly scattering polymers and biopolymers. In single-crystal Adiffraction, sub-(mu)n^3 crystal volumes have been reached for inorganic crystals. Protein Acrystallography has been demonstrated for a lew tenths of (mu)n linear crystal size, which Areduces the crystallization time for many proteins.