Fig. 1: XRD patterns of synthesized samples at various pressures with theoretical analysis of their stability.
From: Synthesis of molecular metallic barium superhydride: pseudocubic BaH12
a Experimental X-ray diffraction pattern from DAC #B1 at 160 GPa and the Le Bail refinement of the pseudocubic Cmc21-BaH12 phase. The experimental data, fitted line, and residues are shown in red, black, and green, respectively. Unidentified reflections are indicated by asterisks. b X-ray diffraction patterns at pressures of 119 to 160 GPa. The inset shows the projection of the Cmc21 structure to the (ac) plane. The hydrogen network is shown by light blue lines. c Convex hulls of the Ba–H system at 100, 150, and 200 GPa calculated with zero-point energy (ZPE) contribution. d Calculated equations of state for different possible crystal modifications of BaH12 (fcc, I4/mmm, and Cmc21) and Ba+nH2. The experimental data are shown by hollow squares.
