Spectral denoising for accelerated analysis of correlated ionic transport

We propose a new general method for analyzing and calculating diffusivity and ionic conductivity in media with strong ionic correlations. Previously, the only two options were the dilute uncorrelated approximation that is rapid but inaccurate, and the exact Green-Kubo method that is prohibitively expensive for complex systems. Our method automatically extracts and utilizes the collective diffusion eigenmodes of the displacement correlation matrix. The proposed approach is universally applicable, simple, and provably superior to previously available methods, exhibiting speed ups of several orders of magnitude. It opens wide opportunities to study correlated diffusion in previously inaccessible complex electrolytes.