High-pressure single-crystal neutron diffraction to 10 GPa by angle-dispersive techniques

Techniques have been developed that allow the measurement of accurate single-crystal neutron-diffraction data at pressures up to 10 GPa, using angle-dispersive methods. High-quality data have been collected up to 10 GPa, to a resolution of sin theta/lambda similar or equal to 1.5 angstrom(-1), from samples of size 3-4 mm(3). This article presents the methods developed to mount and centre the sample accurately on the instrument; to reduce the background and hence increase the precision of the measured reflection intensities; and to increase further the accessible region of reciprocal space with a single sample loading. Developments are also highlighted, with a view to increasing the range of both science and pressures that can be achieved at the Institut Laue-Langevin reactor source using single-crystal techniques.