NONAQUEOUS SYNTHESIS AND CHARACTERIZATION OF A NEW 2-DIMENSIONAL LAYERED ALUMINOPHOSPHATE [AL3P4O16](3-)CENTER-DOT-3[CH3CH2NH3](+)

The compound [Al3P4O16](3-) . 3[CH3CH2NH3](+) has been synthesized fro m the nonaqueous system H3PO4-(iPrO)(3)AlCH3CH2NH2-CH3(CH2)(3)OH. It h as been definitively characterized by single-crystal X-ray diffraction , with space group P2(1)/m and unit cell a = 8.920(2), b = 14.896(2), c = 9.363(2) Angstrom, beta = 106.07(2)degrees, and V = 1191.6(4)Angst rom(3). The structure consists of [Al3P4O16](3-) sheets with a 4 X 6 X 8 network. This contains individual AlO4 and PO4 centered tetrahedral in the ratio of 3/4, in which all AlO4 vertices are shared but each P O4 has one terminal P=O. These are projected alternatively above above below the 2-D sheet and are hydrogen bonded to the ethylammonium ions which serve to template the structure. They give rise to elliptical e ight-membered rings, which have a cavity size of 3.8 x 6.0 Angstrom an d an AAAA stacking sequence. This compound thus strengthens the family of 4 x 6 x 8 and 4 x 6 x 12 nets with AAAA or ABAB stackings for [Al3 P4O16](3-), allowing rationalization based on the amine template lengt h and functional multiplicity. Additional characterizations of the com pound by XRD, SEM, IR spectroscopy, inductive coupled plasma analysis, TGA, and DTA are also described. (C) 1997 Academic Press.