Piperazinium sulfate – selenous acid cocrystal: a new organically templated non-centrosymmetric compound

Abstract A new organically templated hybrid organo-inorganic compound, (C 4 H 12 N 2 )SO 4 ⋅3H 2 SeO 3 , was prepared during systematic studies of sulfate co-crystals with selenious acid. The new compound crystallizes in a non-centrosymmetric space group P 2 1 ( a = 6.2876(2) Å, b = 17.9296(6) Å, c = 7.2701(3) Å, β = 106.979(4)°, R 1 = 0.027) and exhibits a weak SHG activity. The new compound belongs to a rapidly developing family of hydrogen-bonded architectures formed by selenious acid co-crystals. The crystal structure corresponds to a pseudo-layered hydrogen-bonded framework with alternating organic and inorganic “slabs” linked by hydrogen bonds.