Microsymposia C38 Function, S n , that gives both the stoichiometry and aspects of the bond topology of the structures. We may thus write the structuregenerating function, S n , for the biopyribole structures as follows: S n = X i [M (3n-1) Ψ 2(n-1) {T 2n Θ br (3n-1 Θ ap 2n Θ l 2 } 2 ]. This function generates: n = 1, the pyroxenes; for n = 2, the amphiboles; for n = 3, the triple-chain pyriboles; for n = 4, S 4 = X I [M 11 Ψ 6 {T 8 Θ 21 } 2 ]; for n = ∞, the micas. Where N = 2, the general

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... of the T component is {T 2n Θ 5n+2 } which corresponds to the T component of H-layers in the polysomatic H-O-H series in which the ribbons are linked laterally by [5]-or [6]coordinated cations, D, which have the coordination (DΘ l 4 Φ ap Φ t 0-1 ). The general formula for an H layer is [DΦ ap {T 2n Θ br 3n-2 Θ ap 2n Θ l 4 }Φ t 0-1 ], where Φ t after the T component occurs on the outside of the H-layer and is involved in linkage between adjacent H-O-H sheets. The Hlayer links via its apical anions to the O-layer, giving the general formula of an H-O-H sheet as [M 3n+1 DΦ ap This function generates: for n = 1, the group-1 TS-block structures; for n = 2, the astrophyllite-group structures; for n = 3, nafertisite: ideally Na 2 [Fe 2+ 10 O 2 (OH) 6 (Ti 2 {Si 12 O 34 })](H 2 O) 0-2 ; for n = ∞, the micas. We may combine the two generating functions (above) into a single function: that gives all the above structures. This expression also generates mixed-ribbon polysomatic structures. S (1;2+3) = X i [M 13 Ψ 6 {T 10 Θ br 13 Θ ap 10 Θ l 4 } 2 ] gives the chemical composition and structure of the mixed-chain pyribole, chesterite: Mg 4 [Mg 13 (OH) 6 {Si 10 O br 13 O ap 10 O l 4 } 2 ], and S (2;1+4) = X i [M 17 Ψ 10 (D 4 Φ 4 {T 2 O br O ap 2 O l 4 } 2 {T 8 O br 10 O ap 8 O l 4 } 2 )Φ t 0-4 ] gives the chemical composition and structure of the mixed-chain H-O-H mineral, veblenite: KNa(H 2 O) 3 [(Fe 2+ 5 Fe 3+ 4 Mn 6 Ca ) (OH) 10 (Nb 4 O 4 {Si 2 O 7 } 2 {Si 8 O 22 } 2 )O 2 ]. A range of anionic metal-organic framework (MOF) materials has been prepared by combination of In(III) with tetracarboxylate isophthalate ligands. These materials incorporate organic cations, either H 2 ppz 2+ (ppz = piperazine) or Me 2 NH 2 + , that are hydrogen bonded to the pore wall [1], [2]. These cations act as a gate controlling entry of N 2 and H 2 gas into and out of the porous host. Thus, hysteretic adsorption/desorption for N 2 and H 2 is observed in these systems reflecting the role of the bulky hydrogen bonded organic cations in controlling the kinetic trapping of substrates. Post-synthetic cation exchange with Li + leads to removal of the organic cation and the formation of the corresponding Li + salts. Replacement of the organic cation with smaller Li + leads to an increase in internal surface area and pore volume of the framework material, and in some cases to a change in the overall network topology and structure [3]. An increase in the isosteric heat of adsorption of H 2 at zero coverage has also been observed on incorporation of Li + ions, as predicted by theoretical modeling [4], [5], [6]. Furthermore, a new doubly-interpenetrated network system has been identified in which the second net is only partially formed (0.75 occupancy; see Figure) . This material undergoes a structural re-arrangement on desolvation, and shows high selective storage uptake for CO 2 . The structures, characterisation and analyses of these charged porous materials as storage portals for gases are discussed.