PDF and BOO analysis. (A) The PDF curve among all atoms in amorphous nanoparticles. The dashed lines point out the ideal peak positions of MG structure according to the theoretical analysis, which fits well in this specimen. The inset shows the second-peak splitting with a double Gaussian fit (Adapted from ref. [60]. Copyright©2021, Springer Nature). (B) The PDF curves between two types of atoms in an amorphous alloy NP, as listed in the legend. The curves emphasize the irregular behavior of the curve type 33 (Adapted from ref. [60]. Copyright©2021, Springer Nature). (C) The PDF curves of three monatomic amorphous solids and one theoretical simulation structure (Adapted from ref. [61]. Copyright©2022, Springer Nature). (D) The BOO analysis of all atoms in seven amorphous alloy nanoparticles separately. Cu₆₅Zr₃₅ simulated model analysis is presented as a reference. The red dashed lines show the criterion that divides the amorphous and crystal structure (Adapted from ref. [60]. Copyright©2021, Springer Nature).