Fig. 5. High-pressure data of [P_666,14][TCM], [P_666,14][TFSI], [P_666,14][TAU], and [P_666,14][BOB] (from left to right respectively).

a Presents the pressure dependence of conductivity relaxation time measured at various T. Solid lines denote the pVFT fit ${\tau }_{\sigma }={\tau }_0\exp \left(\frac{BP}{P_0-P}\right)$ to experimental data. Dashed lines indicate liquid–liquid transition pressure (P_LL) and τ_σ at LLT. P_g denotes liquid–glass transition pressure. b Presents pressure dependence of apparent activation volume, V^#. The four-time increase in V^# at LLT indicates a formation of nonpolar domains of large scale in liquid 2. c T_LL and T_g as a function of P is presented. The color area on a and c denotes the liquid 1 phase (gray) and glass region (blue). L1 denotes liquid 1 while L2 liquid 2. Source data are provided as a Source Data file.