Nanoparticle Etch Kinetics: Shrinking-Core Dissolution

Splitting a nanoparticle into smaller pieces is only half the story of why nanoscale material behaves so differently from bulk matter — the other half is how fast each piece reacts away once exposed. This simulator fragments a real square atomic lattice into k² equal-mass pieces, then etches every fragment from a reactive interface that recedes inward at a constant velocity, exactly the shrinking-core kinetics used to model interface-limited nanoparticle dissolution and corrosion. Because the time to fully consume a fragment scales directly with its own edge length, smaller fragments disappear in proportionally less time at the very same etch rate — and the live perimeter-to-area readout shows why: as a fragment's remaining core shrinks, its exposed edge relative to what's left inside grows without bound, accelerating the reaction right up to the final atomic layer. A second panel plots the exact discrete atom count against the smooth continuum prediction so you can see how closely a real, small, integer lattice tracks the idealized formula.