catena-Poly[1,2,2-trimethylcyclopentane-1,3-diammonium [aluminate(III)-μ-(hydrogen phosphato)-μ-phosphato]]

In the title compound, {(C8H20N2)[Al(HPO4)(PO4)]}n, the AlIII atom is coordinated by four O atoms from two HPO4 2− and two PO4 3− groups in a distorted tetrahedral geometry. Each AlO4 unit shares four O atoms with four adjacent PO4 units, leading to an anionic chain along [100]. The negative charge of the chain is compensated by doubly protonated camphoric amine cations. N—H⋯O hydrogen bonds connect the cations and the anionic chains. O—H⋯O hydrogen bonds are present in the chain.

In the title compound, {(C 8 H 20 N 2 )[Al(HPO 4 )(PO 4 )]} n , the Al III atom is coordinated by four O atoms from two HPO 4 2À and two PO 4 3À groups in a distorted tetrahedral geometry. Each AlO 4 unit shares four O atoms with four adjacent PO 4 units, leading to an anionic chain along [100]. The negative charge of the chain is compensated by doubly protonated camphoric amine cations. N-HÁ Á ÁO hydrogen bonds connect the cations and the anionic chains. O-HÁ Á ÁO hydrogen bonds are present in the chain.
Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 There are considerable interests in the synthesis of chiral inorganic framework materials for their potential applications in separation and catalysis (Viter & Nagornyi, 2009). Our interest is particularly focused on the synthesis of microporous aluminophosphate. We used organic camphoric amine as the template and hydrothermally synthesized the title compound ( Fig. 1).
The structure consists of aluminophosphate chains of formula [Al(HPO 4 )(PO 4 )] n , running along the a axis, and doubly protonated camphoric amine cations (Fig. 2). The chain is constructed from AlO 4 tetrahedra and PO 4 tetrahedra. Each AlO 4 tetrahedron shares four O atoms with adjacent PO 4 tetrahedra, whereas each PO 4 tetrahedron shares two O atoms with adjacent AlO 4 tetrahedra, leaving the other two O atoms terminal. The structure denotes that AlPO-CSC (Corner-Sharing Chain) is one of the fundamental chains in the known aluminophosphate compounds (Jones et al., 1990;Oliver et al., 1998;Williams et al., 1997). The negative charge of the chain is compensated by protonated organic camphoric amine cations, which are connected to the chains through N-H···O hydrogen bonds (Table 1).

Refinement
H atoms on C and N atoms were positioned geometrically and refined as riding atoms, with C-H = 0.98 (CH), 0.97 (CH 2 ) and 0.96 (CH 3 ) Å and N-H = 0.89 Å and with U iso (H) = 1.2(1.5 for methyl and ammonium)U eq (C,N). Hydroxyl H atom was located from a difference Fourier map and refined as riding, with O-H = 0.96 Å and U iso (H) = 1.5U eq (O). program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008  The asymmetric unit of the title compound. Displacement ellipsoids are drawn at the 50% probability level.  The anionic chain and camphoric amine cation in the title compound.

Special details
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.