APA₂[Zn₃(HPO₄)₄(H₂O)₂], a layered zincophosphate featuring template-to-framework N-H⋯O and "synergic" framework-to-template O-H⋯N hydrogen bonds and C-H⋯O interactions (APA = 2-Amino-1-phenyleneammonium, C₆H₉N₂ ⁺)

The crystal structure of APA₂[Zn₃(HPO₄)₄(H₂O)₂] (APA = 2-amino-1-phenylene-ammonium, C₆H₉N₂⁺) (1), as prepared by a predominantly non-aqueous synthesis, is described and compared to related compounds. 1 is built up from an alternating array of ZnO₄ and HPO₄ tetrahedra sharing vertices as Zn-O-P bonds to generate infinite anionic sheets. Within these sheets, polyhedral 4-, 6- and 8-rings are apparent. The negative charge of the inorganic layer is balanced by singly-protonated APA template cations and water molecules are also present. The components are linked by N_t-H⋯O_f, O_f-H⋯O_w, O_w-H⋯O_f and O_f-H⋯N_t (t = template, f = framework, w = water) hydrogen bonds: The last of these represents an unusual framework-to-template interaction. Weak C_t-H⋯O_f links may also play a role in consolidating the structure. Crystal data: 1 (C₁₂H₂₆N₄O₁₈P₄Zn₃), M_r = 834.36, monoclinic, C2/c (No. 15), Z = 4, a = 20.194 (8) Å, b = 8.682 (3) Å, c = 15.123 (6) Å, β = 91.510 (11)°, V = 2650.5 (17) ų, R(F) = 0.048, wR(F²) = 0.112.