Shadowing and absorption corrections of single-crystal high-pressure data

The effect of shadowing the sample crystal enclosed in the diamond-anvil high-pressure cell (DAC) by the gasket edges, i.e. by the walls of the high-pressure chamber, has been described for unrestricted data-collection procedures. A general vector formalism reveals new features of the shadowing and absorption corrections, depending on the primary beam-DAC-reflection configuration. The corrections apply to the data measured with conventional normal-beam-equatorial diffractometers, or with area-detectors. The simple vector approach optimizes computations and affords straightforward corrections of intensities. Feasibility of enhancing the resolution of numerical integration by applying fine grid divisions, has been discussed.