Extended Data Fig. 8: Evidence supporting the existence of the 6M-TTP clusters in the amorphous structure of Pd-Ni-P alloy by cluster-image comparisons and image simulation of an amorphous structure.

a, A comparison between the medium-range order in the 2D-DF HAADF-STEM image of the 583-K annealed Pd-Ni-P sample and the proposed 6M-TTP cluster. The yellow circles mark the position of the potential 6M-TTP clusters. The image is surrounded by seven enlarged 2D-DF HAADF-STEM images, in which the modelled 6M-TTP cluster and the corresponding STEM simulation results are superimposed. Three major symmetry directions, that is, [100], [110] and [111], can be clearly seen, which are similar to those of 6M-TTP projections. The comparisons are shown in sub-panels (I-II), (III-IV), and (V-VII), respectively. The bottom right panel is the FFT pattern demonstrating amorphous nature. b, A comparison between the medium-range order in the 2D-DF HAADF-STEM image of as-cast Pd-Ni-P sample and the proposed 6M-TTP cluster. The yellow circles mark the position of the 6M-TTP clusters. I-III, Enlarged 2D-DF HAADF-STEM images, in which the modelled 6M-TTP cluster and the corresponding STEM simulation results with [100], [110], and [111] orientations are superimposed, respectively. The bottom right panel is the FFT pattern demonstrating amorphous nature. c, Structure model of the random packed atomic structure with embedded 6M-TTP clusters and d, HREM simulation by multislice technology using xHREM software. Gray balls represent the metal atoms (Pd/Ni), and purple balls are the metalloid atoms (P). The circled regions are the embedded 6M-TTP clusters with [100], [110], and [111] orientations, respectively. e, The enlarged image of Extended Data Fig. 8a.