Fig. 1: Temperature dependence of the atomic dynamics in Pt_42.5Cu₂₇Ni_9.5P₂₁ and Pd_42.5Cu₂₇Ni_9.5P₂₁ supercooled liquids.

a, b Normalized intensity autocorrelation functions measured at various temperatures for Pt_42.5Cu₂₇Ni_9.5P₂₁ (a), and Pd_42.5Cu₂₇Ni_9.5P₂₁ (b) at the wave vector Q of the first sharp diffraction peak (Q_FSDP ≈ 2.8 Å⁻¹ for both systems). c, d Mean relaxation time <τ(Q,T)> of the Pt- and Pd-based alloys measured at the position of the first sharp diffraction peak Q_FSDP at various temperatures T. The solid lines are fits to the Vogel-Fulcher-Tammann equation (see section “Collective particle motion in the supercooled liquid phase”). e, f Temperature dependence of the corresponding exponent of the Kohlrausch-William-Watts equation β(Q,T) for Pt_42.5Cu₂₇Ni_9.5P₂₁ (e) and Pd_42.5Cu₂₇Ni_9.5P₂₁ (f). The dashed line is a guide to the eyes. Error bars indicate the standard error due to fitting of the experimental data using the Levenberg Marquardt algorithm.