Abstract
Molecular sieving occurs when a smaller molecule selectively enters the nanopore. Contrary to this understanding, we find that single-wall carbon nanotubes with a van der Waals pore size of just 0.42 nm readily separate n-hexane from cyclohexane—despite the fact that both molecules are larger than the rigid nanopore. This unexpected observation challenges our current understanding of nanopore selectivity and how molecules may enter a tight channel. In this talk, we will discuss a joint experimental and theoretical study on this phenomenon. The insights may open up new opportunities to engineer nanopore selectivity based on the molecular degrees of freedom.