On the other hand, several studies have instead shown that solution aggregation can be detrimental to charge transport. For instances, Nahid and McNeil et al. have shown that the saturation mobility of P(NDI2OD-T2) OFETs fabricated from aggregated high-molecular weight (MW) polymer solution is lower compared to those fabricated from fully dissolved low-MW polymer solution . The authors hypothesize that the solution aggregates of P(NDI2OD-T2) can suppress long-range LC order and hinders the correlated packing of polymer chains. In contrast, the non-aggregated low-MW polymer solutions enable individual polymer chains to adopt fully extended conformations during spin coating, resulting in higher degrees of correlated long-range order and better performance in OFETs. As another example, our recent work has discovered that isoindigo-bithiophene-based polymer (PII-2T) aggregates into helical nanofibers; the helical structure is unfavorable for intrachain charge transport as compared to more planar counterpart .