Database of Zeolite Structures
 

Framework Type STI
Volumes and areas calculated from the idealized framework model
Occupiable Volume 572.35 Å3 (13.27 %)  
Accessible Volume 572.35 Å3 (13.27 %)  
Occupiable Area 827.65 Å2 (1152.13 m2/g)  
Accessible Area 827.65 Å2 (1152.13 m2/g)  
Specific Occupiable Area 1919.14 m2/cm3    
Specific Accessible Area 1919.14 m2/cm3    
Maximum diameter of a sphere:      
that can be included 6.29 Å
that can diffuse along a:   4.94 Å b:   2.96 Å c:   1.85 Å  


Explanations
Occupiable volume That portion of the available volume within the cell that can be visited by the center of a (spherical) water molecule (radius = 1.4Å). The available volume is the unit cell volume remaining after the van der Waals atomic sphere volumes are subtracted.
Occupiable area The area of that surface visited by the center of the water molecule.
Accessible volume That portion of the occupiable volume that has continuity between all unit unit cells. Some pores/cavities have windows that are too small to allow the water molecule access, and so represent isolated occupiable regions.
Accessible area The area of that surface visited by the center of the water molecule.
Specific occupiable area Occupiable area per unit volume
Specific accessible area Accessible area per unit volume



 

Credits:
These values were calculated by Mike Treacy, Arizona State University, using his codes "TOTOPOL" and "DelaneysDonkey".
see also:
M. D. Foster, I. Rivin, M. M. J. Treacy and O. Delgado Friedrichs,
A geometric solution to the Largest-Free-Sphere problem in zeolite frameworks,
Microporous and Mesoporous Materials, 90 32-38 (2006).