[H₃N(CH₂)₂NH₃]_0.5[BePO₄], a ­beryllophosphate analogue of ­aluminosilicate zeolite gismondine

[H₃N(CH₂)₂NH₃]_0.5[BePO₄] is the first organically templated beryl­lophosphate to crystallize with an aluminosilicate zeolite topology. A three-dimensional network of BeO₄ and PO₄ tetrahedra corresponding to the gismondine (GIS) framework encapsulates disordered ethyl­enedi­ammonium cations.