Fig. 1: Results of XRD measurements on the sample of Re and N2 pulsed laser-heated in dsDAC #1.
a, X-ray 2D map showing the distribution of different phases (recrystallized Re and Re7N3) in the pressure chamber of dsDAC #1. Each pixel on the map corresponds to a 2D XRD pattern collected at the Frelon 4M detector at the ID11 beamline at ESRF (beam size FWHM approximately 0.45 × 0.45 μm2, λ = 0.3099 Å). The map covers the whole pressure chamber (21.5 × 21.5 μm2, steps of 0.5 μm in both directions, 10-s acquisition time per frame). The total collection time was about 8 h. The colour intensity is proportional to the intensity of the following reflections: the (100) reflection of the Re gasket for the dark blue region; the (101) reflection of Re for the light blue region (inside the sample chamber); the inset colour bar corresponds to the sum of intensities of (202) and (420) reflections of Re7N3. b, Example of an as-collected diffraction image with diffraction lines and spots of Re (a = 2.2269(4) Å, c = 3.5702(15) Å) and Re7N3 (a = 6.2788(2) Å, c = 4.000(2) Å). The characteristic diffraction image shown in b is highlighted with a white rectangle in a. c, d, The reconstructed reciprocal lattice planes of Re (c) and Re7N3 (d). In c, d, the reflections of Re and Re7N3 are marked by yellow and green circles, respectively, and the corresponding hkl are given. Powder diffraction lines are due to the Re gasket and untransformed rhenium. In b–d, blue circles and the blue rectangle indicate parasitic reflections from diamond anvils.
