2,2′-bipyridyl (bpy) and 1,10-phenanthroline (phen) intercalate topotactically into Ti(H2PO4)(PO4)·2H2O (γ-titanium phosphate, γ-TiP), the aromatic rings undergoing hydration owing to the strongly acidic character of the > P(OH)2 groups. For protonated phen, a ‘slotted’ assembly in the interlayer phosphate surface is given, via NH+⋯ HO —P hydrogen bonding (from indirect spectroscopic results and TG /DSC). Instead, protonated bpy adopts a slanted orientation within the layers, as does 2,9-dimethyl-1,10-phenanthroline (dmphen) which remains unprotonated. These differing assemblies lead to differing accessibilities of intercalated amine to metal ion (dmphen > bpy > phen) as confirmed by Cu2+ uptake diffusion rates. Cation exchange of Co2+, Ni2+ and Cu2+-exchanged composites do not give coordination pillaring, even after dehydration of the materials. Ag+ exchanges with Ti(H2PO4)(PO4)(phen)0.44·2.5H2O and Ti(H2PO4)(PO4)(dmphen)0.23·2.2H2O to give highly expanded composites (d002= 20–21.3 A). The former has high thermal stability, decomposing only at > 450 °C, and may be considered a pillared material. Low Ag+-loaded forms give time-dependent staging, ascribed to intralayer Ag+ diffusion. Ag+-phen·γ-TiP materials show enhanced selectivities for Cu2+(Cu2+≫ Ni2+= Co2+) from binary, ternary and quaternary mixtures and the anhydrous Ni2+-exchanged material has a square-planar coordination. Intralayer coordination models are suggested.