Fig. S1.

(A–C, Top) Base particles colored according to their ${\overline{q}}_6$ bond parameter; (Middle) the phase diagram for our simulation system; (Bottom) ${\overline{q}}_6$ histograms. (A) The liquid phase at $\varphi =0.060$. (B) Phase coexistence of liquid at the BCC phase at $\varphi =0.063$. (C) A BCC phase at $\varphi =0.0656$. Histograms are an average over 90 snapshots separated by $\mathrm{\Delta }t=2\cdot {10}^1$ ${\tau }_b$.