diameter of ethane = 5.0 Angstroms
Ethane cannot pass Ethane. Methane passes Methane. Methane passes Ethane.
diameter of ethane = 6.0 Angstroms
Ethane cannot pass Ethane. Methane passes Methane. Methane cannot pass Ethane.
These are movies of the motion of a mixture of Methane and Ethane
in the one-dimensional pores of the
molecular sieve, AlPO4-5. The molecular sieve is not shown.
(See the interactive section of this site to view the crystal structure of
AlPO4-5.
In this sequence, for the smaller ethane diameter, since methane passes ethane, the methane
retains its ordinary diffusive behavior. Hwever, for the larger ethane size, the methane
cannot pass ethane. There are clusters of
methane, sandwiched between ethane molecules. The clusters undergo a single-file motion of clusters.
This work was done by David Keffer at the University of Tennessee, 1998.
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