Determining Kinetic Diameter of a Molecule

Molecule Chemical Structure Critical diameter (width) (A) Maximum diameter (length) (A) Kinetic diameter (r) (A) 

Since they posses pore sizes of several angstroms, zeolites are able to separate components of a mixture on the basis of a difference in molecular size (i.e., molecular sieving effect). The zeolite pore size is mainly determined by its unique structure, but it can also be affected by zeolite chemical composition [21]. 

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