A 2D hybrid organic-inorganic perovskite, when melted and cooled into a glass, produces an amorphous material harder than the crystalline form of the exact same compound. The glass has a higher Young's modulus than its own crystal. Disorder outperforms order.
The conventional hierarchy is clear: crystals are mechanically superior because their atomic regularity eliminates weak points. Glass, being disordered, should be weaker. But regularity includes regular slip planes — crystallographic planes along which dislocations can propagate and cracks can run. The crystal's order provides the highways for its own fracture.
The glass retains partial metal-halide-metal connectivity between neighboring octahedra and residual structural correlations. It is not fully random — it is frustrated. Local order persists but long-range periodicity is broken. This frustrated structure has fewer slip planes and fewer pathways for crack propagation. The disorder interrupts the highways that regularity would provide.
The result is a material where perfect order creates pathways for its own failure. The crystal is weaker precisely because it is more ordered — the regularity that defines it also defines the directions in which it can be broken. The glass, lacking those regular directions, lacks the preferred failure modes.
This is a structural argument for why messy systems can be more resilient than neat ones. Not despite their disorder but because of it. Order transmits stress along defined channels. Disorder distributes stress across undefined ones. The system with no preferred direction of failure has no preferred direction of failure.