Again, this length scale is interpreted as representing the size of inter-fibrillar voids/domains embedded in a nanofibrillar mesh. In keeping with our above qualitative analysis, the as cast (neat) and dedoped samples gave similar characteristic length scales, 128 and 132 Å, respectively. The exposed and redoped samples were likewise similar, with characteristic length scales of 78.0 and 66.7 Å, respectively. The ~50-65 Å difference between exposed/redoped and neat/dedoped is ascribed to a contraction of the inter-fibrillar void/domain. This inter-fibrillar void/domain contraction is inversely correlated with a crystallite expansion (~12%) previously determined by in situ GIWAXS. As the acid treatment produces highly crystalline nanofibrils, it is presumed that the nanofibrillar expansion is likely equivalent to the crystallite expansion.