Hard Disk Packing — Crystallization & Jamming

2D hard disks: KTHNY melting, hexatic order, and jamming transition

60 0.00
In 2D, hard disks undergo the KTHNY (Kosterlitz-Thouless-Halperin-Nelson-Young) melting transition via two continuous transitions: solid → hexatic (at phi_1~0.70) → liquid (at phi_2~0.72). The hexatic phase has quasi-long-range orientational order. Jamming occurs near phi_J~0.84 (random close packing in 2D).