UT-7 and UT-8 (University of Toronto, structure numbers 7 and 8) are two novel aluminophosphate
materials prepared under non-aqueous conditions. Their structures, extended in one
and two dimensions, respectively, have been solved by single-crystal X-ray diffraction
and characterized by a variety of methods including powder X-ray diffraction (PXRD),
insitu high-temperature PXRD, thermogravimetric analysis (TGA), energy dispersive
X-ray analysis (EDX), and scanning electron microscopy (SEM). UT-7 ([Al(3)P(5)O(20)H](5)(-)[C(7)H(13)NH(3)(+)](5),
triclinic space group P&onemacr;, Z = 2, a = 10.118(3) Å, b = 15.691(4) Å, c = 18.117(3)
Å, alpha = 72.91(2) degrees, beta = 85.18(2) degrees, gamma = 79.49(2) degrees ) is
built of polymeric one-dimensional chain units, hydrogen-bonded into anionic layers
that are charge-compensated by interlamellar cycloheptylammonium cations. UT-7 is
isostructural to our previously discovered UT-3 chain structure, isolated in the analogous
cyclopentylamine system. UT-8 ([Al(3)P(4)O(16)](3-)[C(4)H(7)NH(3)(+)](2)[C(5)H(10)NH(2)(+)],
monoclinic space group P2(1), Z = 2, a = 8.993(4) Å, b = 14.884(8) Å, c = 9.799(9)
Å, beta = 103.52(3) degrees ) is a two-dimensional net isostructural to several previously
reported [Al(3)P(4)O(16)](3)(-) layers. The interlayer region of UT-8 is occupied
by two different cyclic organic amine species, namely piperidinium and cyclobutylammonium.
To our knowledge, this is the first report of the crystal structure of an aluminophosphate
material containing cyclobutylammonium or a mixture of cyclic amines. Interestingly,
UT-7 is observed to thermally transform in the solid state to an as yet unknown layered
material that can be independently synthesized in a similar synthetic system. In the
same way as UT-3 transforms to the UT-4 layered phase, we believe UT-7 transforms
to a layered material by means of a chain to layer transformation.