[H3N(CH2)2NH3]0.5[BePO4], a ­beryllophosphate analogue of ­aluminosilicate zeolite gismondine

Hydro­thermally prepared ethyl­enedi­ammonium beryl­lo­phosphate, (C₂H₁₀N₂)_0.5BePO₄], is an analogue of aluminosilicate zeolite gismondine. A three‐dimensional network of vertex‐sharing BeO₄ and PO₄ tetrahedra d_av(Be—O) = 1.618 (3) Å, d_av(P—O) = 1.5246 (14) Å and θ_av(Be—O—P) = 139.8°] encapsulates the disordered ethyl­enedi­ammonium cations in an eight‐ring channel system.