To understand the changes occurring during the plateau region, ∆𝜌(𝑟) is again deconvoluted into broad and sharp components. These are shown in Figure cluster formation during the plateau region with larger clusters forming in HCs prepared at higher pyrolysis temperatures. Furthermore, the size of the clusters closely matches the largest pore sizes that are filled for each HC, suggesting that the correlations observed in the broad component of the ∆𝜌(𝑟) originate from the largest sodium clusters. Although PDF analysis is primarily sensitive to pair correlations arising from the largest clusters, we expect a cluster size distribution for each HC that matches the distribution of filled pore sizes.