Short-range electrostatic screening in ionic liquids as inferred by direct force measurements
In the last decade, conflicting experimental reports of long-range interactions in #ionicLiquids (ILs) and concentrated #electrolytes have puzzled theory and numerical simulations.
The discrepancy lies in nonequilibrium effects as evidenced by our rigorous measurement protocols using complementary advanced Surface Force Apparatuses. ILs screening is genuinely short-range under conditions approaching thermodynamic equilibrium. Their decay lengths (~0.5 nm) match the theoretical predictions. Conversely the further from equilibrium the larger interaction extents. These arise from background drift rates with various relaxations spanning two orders of magnitude in time scale. The IL behavior is reminiscent of slow relaxation dynamics in glasses, thin polymer films, historical paintings, and granular media.
