The crystal structure of the microporous solid MAPO-39 (ATN) refined from single crystal diffraction data

• Published in: Zeitschrift für Kristallographie. Crystalline materials Vol. 214; no. 3; pp. 154 - 159
• Format: Journal Article
• Language: English
• Published: De Gruyter Oldenbourg 01.03.1999
• ISSN: 2194-4946; 2196-7105
• DOI: 10.1524/zkri.1999.214.3.154

MAPO-39 is a crystalline magnesiumaluminophosphate with an idealized framework composition Al MgHP and a crystal structure corresponding to zeolite framework topology ATN, = 974.0, tetragonal, space group 4/ , = 13.2088(2) Å, = 5.2771(2) Å, = 920.71(6) Å , = 1, = 1.754 Mg m , (Mo ) = 0.65 mm , (Mo ) = 0.71069 Å, (Cu ) = 6.30 mm , (Cu ) = 1.5418 Å, (000) = 479. The intensities of 9733 reflections were measured on a single crystal X-ray diffractometer with Mo , radiation, and 3253 reflections with Cu radiation. Both data sets were combined and 1304 averaged unique intensities obtained, refinement on | |, = 0.093, = 0.024, including all unobserved and weak . A previously published structural model of MAPO-39 with wide 1-dimensional pores outlined by 8-rings in space group [unk] and based on X-ray powder diffraction data has been essentially confirmed for MAPO-39. It did not prove possible to locate precisely the template molecules in the wide pores of MAPO-39, most probably because these molecules are highly disordered. The narrower channels outlined by saddle-shaped 8-rings are small enough to be locally plugged by inverted phosphate and aluminate tetrahedra which stick out into the 1-dimensional pore. The magnesium atoms in MAPO-39 replace statistically part of the aluminium atoms in the framework. The net of primary bonds P–O and Al–O of MAPO-39 corresponds to Net 8′ predicted by Wells (Three-dimensional nets and polyhedra, New York, Wiley, 1977, p. 134) as a possible tetrahedral framework. It is the tetragonal equivalent of the hexagonal cancrinite net.