Synthèse et résolution structurale d’un nouveau sel à transfert de charge associant l’anion organique ABTS2– et son radical ABTS•– avec le cation inorganique La3+ : La3(ABTS)5(H2O)31

Abstract

By the electrocrystallization technique, it has been possible to synthesize a new charge transfer salt, associating the organic anion ABTS^2–, the radical anion ABTS^– (ABTS is the commercial name of the diammonium salt of the 2-2’ azinobis–3 ethyl benzothiazoline sulfonate), and the inorganic cation La³⁺. From single crystal X-ray diffraction data, the crystal structure was solved at 200 K. La₃(ABTS)₅(H₂O)₃₁ belongs to the triclinic symmetry space group $P\overline{1}$ with the cell parameters: a = 18.342(4) Å, b = 17.720 (4) Å, c = 20.394(4) Å, α = 87.97(3)°, β = 79.08(3)°, γ = 85.21(3)°, V = 6 850(2) Å³ and Z = 2. The crystalline network reveals a two-dimensional character based on an alternation of organic and inorganic layers. A valence bond calculation corresponds to a lanthanum in a (+III) oxidation state. This compound is a mixed anionic valence salt, and in accordance with the charge equilibrium, its formulation must be written (La³⁺)₃(ABTS^2–)₄(ABTS^•–)₁(H₂O)₃₁.