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Using X-ray Powder Diffraction to Determine the Structure of VPI-5 - A Molecular Sieve with the Largest Known Pores

Published online by Cambridge University Press:  06 March 2019

Cyrus E. Crowder ,
Juan M. Garces  and
Mark E. Davis
Cyrus E. Crowder
Affiliation:
Analytical Sciences, 1897 Bldg. Dow Chemical Co., Midland, MI
Juan M. Garces
Affiliation:
Central Research, 1776 Bldg. Dow Chemical Co., Midland, MI
Mark E. Davis
Affiliation:
Virginia Polytechnic Institute Blacksburg, VA
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Extract

The synthesis of a new family of aluminophosphate-based molecular sieves containing pores defined by 18 tetrahedrally linked atoms has been described by Davis et al at Virginia Polytechnic Institute (VPI). This development reprsents the first reposted synthesis of a moleoular sieve with pores larger than those defined by 12 tetrahedrally linked atoms. This material has been shown to readily absorb triisopropyl benzene and exhibits a pore size distribution, determined from, its argon adsorption isotherm, which suggests the existence of molecular sieve pores larger than those found in known molecular sieves. Confirmation of a pore defined by 18 tetrahedrally linked aluminum and phosphorus atoms was accomplished by crystallographic structure determination using X-ray powder diffraction data. Single crystal methods were impossible due to an inability to synthesize crystals of suitable size. Details of the structure determination are reported in this work.

Type
VIII. Applications of Digitized XRD Patterns
Information
Advances in X-Ray Analysis , Volume 32: Thirty-Seventh Annual Conference on Applications of X-ray Analysis, August 1-5, 1988 , 1988 , pp. 507 - 514
Copyright
Copyright © International Centre for Diffraction Data 1988

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References

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