Synthesis and Crystal Structure of New Hydrated Lead Selenite Nitrate Pb₄(SeO₃)₃(NO₃)₂·2H₂O

The synthesis and crystal structure of new hydrated lead selenite nitrate Pb₄(SeO₃)₃(NO₃)₂·2H₂O (1) are reported. The crystal structure of 1 ( \(P\bar{1}\) , a = 7.2590(2) Å, b = 7.6454(2) Å, c = 14.7293(4) Å, α = 84.386(2)°, β = 78.311(2)°, γ = 83.643(2)°, V = 793.18(4) Å³, R₁ = 3.1%) belongs to a new structure type. It is based on a porous framework composed of [Pb₄(SeO₃)₃]²⁺ layers strongly bound via nitrate anions. Water molecules are located in the channels. Stereochemically active electron pairs of SeO₃E groups are directed toward each other. The structure of 1 is compared with similar architectures involving Pb²⁺ and Se⁴⁺ cations.