Cluster modelling of amorphization pathways in nanostructured arsenic monosulphide

Competitive amorphization scenarios in arsenic monosulphide AsS under nanostructurization from directly-synthesized β -As 4 S 4 polymorph are identified employing ab-initio quantum-chemical modelling route with cluster-simulation code CINCA. Geometrically-optimized configurations of As 4 S 4 cage-like molecule and its network-forming derivatives responsible for amorphization are simulated and parameterized. Most plausible are found to be single-broken As 4 S 4 clusters keeping one hexagon and two adjacent pentagons in atomic arrangement, which are responsible for uncontrolled amorphization in directly-synthesized β -As 4 S 4 polymorph. Completely-polymerized triple- and quadruple-broken As 4 S 4 clusters in chain configurations without any small-ring entities are character for milling-driven amorphization in monoparticulate β -As 4 S 4 - and biparticulate β -As 4 S 4 -Fe 3 O 4 composites. In contrast, in triparticulate 1⋅ β -As 4 S 4 -4⋅ZnS-1⋅Fe 3 O 4 solution, the amorphizing network is built of double-broken As 4 S 4 molecules keeping pentagon-type rings. Combined configuration-enthalpic model showing amorphization diversity in mechanoactivated arsenic monosulphide is developed.