Amorphization scenarios in multiparticulate grinding media composed of As4S4/ZnS/Fe3O4 nanocomposites driven by high-energy ball mechanical milling are identified employing the X-ray powder diffraction analysis on intermediate-range ordering in the generated amorphous phase. This amorphous phase is supposed to be nucleated heterogeneously from grain boundaries of β-As4S4 crystallites followed by penetration deeply into grain interior, stabilizing the crystalline-amorphous core-shell structure of the fine-grained nanoparticles. Coexistence of nanocrystalline nc-β-As4S4 and amorphous arsenic monosulphide a-AsS phases is crucial feature of these nanocomposites, the amorphous substance being generated continuously due to re-amorphization of disordered phase initially existed in arsenic sulphide prepared by synthesis from elements and direct milling-driven vitrification of nc-β-As4S4. In monoparticulate β-As4S4-based and biparticulate As4S4/Fe3O4 nanocomposites, the amorphizing configurations are composed of single- and triple-broken chain-like network clusters. Under stronger conditions realized in the grinding medium composed by hard nanoparticles biased by their sizes in respect to 20:1 rule, as in triparticulate 1⋅As4S4-4⋅ZnS-1⋅Fe3O4 nanocomposite, the amorphization scenario differs being activated by double-breaking of intramolecular covalent bonds within As4S4 cage-like molecules. This effect is identified as nanocrystalline nc-ZnS-assisted milling-driven arsenic monosulphide amorphization in triparticulate 1⋅β-As4S4-4⋅ZnS-1⋅Fe3O4 nanocomposite solution.
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