AimatraLab Alloy Builder

The all-site alloy path uses native SCRAPs C++ Hybrid Cuckoo Search; the V2 single-active-sublattice path uses sqsgenerator 0.5.6. Both optimize occupations on fixed geometry, without energy calculation, structure relaxation or property prediction. Hamilton largest remainders only allocate composition ratios to integer atom counts.

Each input must pass import, coordination and periodic-adjacency checks. One active pool shares one target composition; multiple independently constrained pools are not exposed. A high-entropy modelling purpose does not establish chemical plausibility or high-entropy stability for every element combination.

Supports 2–2048 fully periodic sites, 2–8 target elements and up to five shells, each with uniform nonzero coordination. Positive ratios become integer populations through Hamilton largest remainders; inspect actual composition. The HCP template is a close-packed atomic lattice.

SCRAPs exposes population, MC and global/local search budgets, seed and shell weights. Sublattice mode exposes sampling budget, seed, shells and weights, with a default distance-clustering tolerance of 0.03 Å. Larger budgets do not guarantee zero error or a fixed runtime. Both methods use one serial native worker.

Sublattice import rejects partial/mixed occupancy, disorder and ambiguous CIFs; Selective Dynamics constraints are unsupported. Native sqsgenerator adjacency must match the full periodic-image graph. Unrepresentable repeated-image bonds or self images are rejected; fewer shells or an explicitly enlarged cell may be required.

Strict V2 checks may conservatively reject some equivalent lattice-wrap representations at exact boundary coordinates. These checks were not weakened; arbitrary CIF input is not guaranteed to succeed.

The two methods use different objective functions, so their values are not directly comparable. Signed SRO is retained; finite cells may not reach zero. A validation badge records structural and numerical consistency checks; same-seed reproducibility is scoped to the same implementation and environment.

Ball-stick, spheres, wireframe and coordination polyhedra; a/b/c or custom [uvw] views, display repetition, element visibility and colours/radii, labels and cell/axis controls, a larger window, and PNG / TIFF image export (transparent backgrounds for PNG only).

Display copies, distance-based links and convex polyhedra affect the view only. They do not change the scientific structure, composition or export, or validate chemical coordination or energy.

The application uses a modified serial SCRAPs derivative; no endorsement by the original authors or institutions is implied. Both backends retain their method and license attribution.

1. SCRAPs / Hybrid-Cuckoo-Search
2. Singh et al. Accelerating computational modeling and design of high-entropy alloys. Nature Computational Science 1, 54–61 (2021). DOI: 10.1038/s43588-020-00006-7
3. sqsgenerator: official SRO and objective definitions